This document provides information on qualitative analysis in chemistry. It discusses qualitative versus quantitative analysis and describes tests to identify various ions including aluminum, calcium, copper, iron(II), iron(III), ammonium, chloride, bromide, and iodide. It also discusses using sodium hydroxide solution to test for cations, qualitative tests before quantitative tests, flame tests, and testing water for hardness. The key points covered in 3 sentences are: qualitative analysis identifies what substances are present while quantitative determines amounts, common cation tests use sodium hydroxide and anion tests use acids and silver nitrate, and hard water contains magnesium and calcium ions which affect lathering of soap.
Hard water contains dissolved salts like calcium and magnesium that cause soap to produce less lather. The hardness can be temporary or permanent depending on the type of salts. Common methods to soften hard water include distillation, soda process, and permutit process which use chemicals or ion exchange to remove calcium and magnesium ions. Hardness is measured using a titration with EDTA and an indicator and is expressed in units of milliequivalents per liter which corresponds to parts per million of calcium carbonate.
Iodometry and iodimetry are indirect titration methods that use iodine. In iodometry, an oxidizing agent reacts with excess potassium iodide to liberate iodine, which is then titrated against a standard reducing agent like thiosulphate. Iodimetry directly titrates a reducing analyte against a standard iodine solution. Starch indicator turns blue or violet in the presence of iodine but is colorless when all iodine reacts at the endpoint of the titration. These methods are used to determine the concentration of various chemicals like vitamin C and thiosulphate.
Qualitative tests for elements in organic compoundsAbigail Sapico
This document outlines qualitative tests for carbon, hydrogen, oxygen, nitrogen, halogens, and sulfur in organic compounds. Carbon and hydrogen are detected by heating compounds with CuO and observing the formation of calcium carbonate and water droplets. Oxygen is detected using ferrox paper or iron(III) hexathiocyanatoferrate(III) solutions, which turn red in the presence of oxygen. Nitrogen, halogens, and sulfur require sodium fusion to convert them to inorganic ions before qualitative testing, such as using Prussian blue for nitrogen or lead sulfide for sulfur.
This document provides information about qualitative analysis of common anions and cations. It describes a series of chemical tests to identify various ions by observing reactions such as formation of precipitates or gases. For example, chloride ions are identified by the formation of a white precipitate with silver nitrate that dissolves in dilute ammonia. The document also lists the expected observations for ions such as sulfate, sulfite, carbonate, hydrogen carbonate and nitrate. Finally, it presents the analysis of an unknown salt and identifies it as chromium (III) carbonate based on the observed green precipitate and reactions.
Inorganic salts used in Tanning of Hides or skinKamruzzaman Khan
This presentation discusses inorganic salts used in tanning leather. It describes the tanning process and various stages where salts are used, including curing, soaking, liming, de-liming, pickling, and chrome tanning. Specific salts used in each stage are identified, such as sodium chloride in curing, sodium carbonate in soaking, and chromium sulfate in chrome tanning. The document also provides details on chromium and its behavior in solutions, discussing its common oxidation states and stable forms. Finally, it mentions complex forms of trivalent titanium salts like potassium hexafluorotitanate.
This document is a chemistry investigatory project report on the preparation of potash alum from aluminium scraps. It includes an introduction describing alums and their uses, the aim of preparing potash alum, a list of required apparatus and materials, theoretical background on the reactions involved, step-by-step procedures followed, observations recorded, and conclusions drawn. The student expresses gratitude to teachers and principals for their support and guidance in completing the project.
This chemistry quiz contains 25 multiple choice questions testing knowledge of chemical reactions and compound identification. Questions ask students to identify products of reactions between acids and bases or salts, such as reactions that produce gas, change in pH, or precipitates. Other questions test the ability to deduce the identity of a compound based on solubility, color changes from reagents, or other evidence from chemical tests. The final questions cover topics like the best methods and reagents for preparing specific salts like calcium sulfate, barium sulfate, or those insoluble in water.
The document describes procedures for determining the available chlorine content in a bleaching powder sample using iodometric titration. Key steps include:
1. Standardizing a sodium thiosulfate solution by titrating it against a primary standard potassium dichromate solution in the presence of excess potassium iodide.
2. Dissolving a bleaching powder sample in water and liberating chlorine by adding acetic acid.
3. Reacting the liberated chlorine with excess potassium iodide to generate iodine, then titrating the iodine with the standardized sodium thiosulfate solution.
4. Calculating the available chlorine content based on the titration
Hard water contains dissolved salts like calcium and magnesium that cause soap to produce less lather. The hardness can be temporary or permanent depending on the type of salts. Common methods to soften hard water include distillation, soda process, and permutit process which use chemicals or ion exchange to remove calcium and magnesium ions. Hardness is measured using a titration with EDTA and an indicator and is expressed in units of milliequivalents per liter which corresponds to parts per million of calcium carbonate.
Iodometry and iodimetry are indirect titration methods that use iodine. In iodometry, an oxidizing agent reacts with excess potassium iodide to liberate iodine, which is then titrated against a standard reducing agent like thiosulphate. Iodimetry directly titrates a reducing analyte against a standard iodine solution. Starch indicator turns blue or violet in the presence of iodine but is colorless when all iodine reacts at the endpoint of the titration. These methods are used to determine the concentration of various chemicals like vitamin C and thiosulphate.
Qualitative tests for elements in organic compoundsAbigail Sapico
This document outlines qualitative tests for carbon, hydrogen, oxygen, nitrogen, halogens, and sulfur in organic compounds. Carbon and hydrogen are detected by heating compounds with CuO and observing the formation of calcium carbonate and water droplets. Oxygen is detected using ferrox paper or iron(III) hexathiocyanatoferrate(III) solutions, which turn red in the presence of oxygen. Nitrogen, halogens, and sulfur require sodium fusion to convert them to inorganic ions before qualitative testing, such as using Prussian blue for nitrogen or lead sulfide for sulfur.
This document provides information about qualitative analysis of common anions and cations. It describes a series of chemical tests to identify various ions by observing reactions such as formation of precipitates or gases. For example, chloride ions are identified by the formation of a white precipitate with silver nitrate that dissolves in dilute ammonia. The document also lists the expected observations for ions such as sulfate, sulfite, carbonate, hydrogen carbonate and nitrate. Finally, it presents the analysis of an unknown salt and identifies it as chromium (III) carbonate based on the observed green precipitate and reactions.
Inorganic salts used in Tanning of Hides or skinKamruzzaman Khan
This presentation discusses inorganic salts used in tanning leather. It describes the tanning process and various stages where salts are used, including curing, soaking, liming, de-liming, pickling, and chrome tanning. Specific salts used in each stage are identified, such as sodium chloride in curing, sodium carbonate in soaking, and chromium sulfate in chrome tanning. The document also provides details on chromium and its behavior in solutions, discussing its common oxidation states and stable forms. Finally, it mentions complex forms of trivalent titanium salts like potassium hexafluorotitanate.
This document is a chemistry investigatory project report on the preparation of potash alum from aluminium scraps. It includes an introduction describing alums and their uses, the aim of preparing potash alum, a list of required apparatus and materials, theoretical background on the reactions involved, step-by-step procedures followed, observations recorded, and conclusions drawn. The student expresses gratitude to teachers and principals for their support and guidance in completing the project.
This chemistry quiz contains 25 multiple choice questions testing knowledge of chemical reactions and compound identification. Questions ask students to identify products of reactions between acids and bases or salts, such as reactions that produce gas, change in pH, or precipitates. Other questions test the ability to deduce the identity of a compound based on solubility, color changes from reagents, or other evidence from chemical tests. The final questions cover topics like the best methods and reagents for preparing specific salts like calcium sulfate, barium sulfate, or those insoluble in water.
The document describes procedures for determining the available chlorine content in a bleaching powder sample using iodometric titration. Key steps include:
1. Standardizing a sodium thiosulfate solution by titrating it against a primary standard potassium dichromate solution in the presence of excess potassium iodide.
2. Dissolving a bleaching powder sample in water and liberating chlorine by adding acetic acid.
3. Reacting the liberated chlorine with excess potassium iodide to generate iodine, then titrating the iodine with the standardized sodium thiosulfate solution.
4. Calculating the available chlorine content based on the titration
This document discusses the reactions and properties of aliphatic alcohols. It outlines five main reactions: 1) replacement of hydrogen by sodium or other active metals to form alkoxides, with reactivity following 1o > 2o > 3o alcohols; 2) replacement of hydroxyl with halogen (Lucas test) with reactivity 3o > 2o > 1o alcohols; 3) oxidation to aldehydes and ketones using chromic acid or other oxidizing agents; 4) esterification with carboxylic acids to form esters; and 5) selective oxidation of methyl alcohol to formaldehyde using a copper catalyst.
Qualitative analysis of group 4 cationsJessa Arino
The Group IV cations are Ba2+, Sr2+, Ca2+.
These metals form chlorides, sulfides and hydroxides that are soluble under that prevail in the precipitations of Group I, II, and III.
Salt analysis involves identifying the cation and anion in an inorganic salt through a series of confirmatory tests. Tests are done by dissolving the salt in water and adding other substances to look for precipitates or color changes. For example, adding barium chloride to the water extract will form a white precipitate confirming the presence of a sulfate anion. Similarly, adding sodium hydroxide and Nessler's reagent can confirm the presence of an ammonium cation through the formation of a yellow or brown precipitate. The document then outlines the specific confirmatory tests used to identify 11 common cations and 12 common anions through characteristic reactions.
This document provides information on iodine titrations, including how they are used for both direct (iodimetry) and indirect (iodometry) titrations. It discusses the solubility of iodine, conditions and precautions for iodine titrations, various methods for determining the endpoint, and applications like assaying ascorbic acid, potassium permanganate, and other compounds. The document also describes how iodine solutions are standardized, often using sodium thiosulfate, as well as how sodium thiosulfate itself must be standardized due to its instability.
The document outlines methods for preparing specified salts through various chemical reactions. It discusses using precipitation reactions when salts are insoluble and acid-base reactions when salts contain sodium, ammonium, or potassium ions. The document provides examples of reacting acids with metal oxides, metals, and metal carbonates to produce salts. It also gives guidance on purification techniques like filtration, washing, drying, heating, cooling/crystallization after reactions. Finally, it includes 5 examples of stoichiometric calculations to determine moles, masses or volumes of reactants and products in salt forming reactions.
This document provides information on common cation and anion tests in chemistry. It lists several cations (aluminum, ammonium, calcium, copper, iron, zinc, lead) and their reactions when aqueous sodium hydroxide or ammonia is added. Precipitates formed are identified. It also lists several anions (carbonate, chloride, iodide, nitrate, sulfate) and their confirmatory chemical tests involving reactions like the formation of gases, precipitates with silver or barium salts, or color changes. The document serves as a reference for students to identify common metal cations and inorganic anions through characteristic chemical reactions.
Preparation of potash alum from aluminium scrapSwaroop Puhan
This document outlines the procedure for preparing potash alum from aluminum scrap. It begins with introducing the uses of alum and its chemical formula. The aim is to prepare potash alum (K2SO4.Al2(SO4)3.24H2O) from aluminum scrap through a series of chemical reactions. The required apparatus, theory, reactions, procedure, observations and conclusions are described in detail. Safety precautions are mentioned and references consulted are listed in the bibliography.
Analytical Procedures in Elemental Impuritiesumaiya fatima
This document discusses analytical procedures for determining elemental impurities like arsenic, lead, and mercury. It provides details on the methodology and reagents used for arsenic detection using the molybdenum blue method and atomic absorption spectrometry. For lead, the dithizone method is described where lead ions form a brown colloid with dithizone. Mercury detection uses the mercury(II) thiocyanate method where chloride ions displace thiocyanate and form a colored complex with iron(III). Spectrophotometric techniques are used for quantification and calibration curves.
This document provides an overview of qualitative inorganic analysis for identifying anions present in compounds. It discusses preliminary and confirmatory tests for several common anions including carbonate, nitrite, acetate, sulfide, sulfite, chloride, bromide, iodide, nitrate, and oxalate. Tests involve observing reactions, such as gas evolution or precipitate formation, when the sample is treated with acids or reagents. Positive test results are indicated by characteristic observations that confirm the presence of the suspected anion.
1. The document summarizes a lab report for a qualitative analysis experiment identifying inorganic compounds through precipitation reactions.
2. Key reactions identified calcium, copper, lead, carbonate, chloride, and sulfate ions based on the color and solubility of precipitates formed when the unknown compounds were reacted with specific reagents.
3. The experiment allowed the student to gain experience using common techniques to identify inorganic cations and anions through observation and interpretation of precipitation results.
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
Oxyacids of sulphur are sulphur, hydrogen and oxygen containing compounds. Oxyacids of sulphur are sulphurous acid, sulphuric acid, peroxomonsulphuric acid, peroxodisulphuric acid, thiosulphuric acid, dithionous acid, dithionic acid, polythionic acid and pyrosulphuric acid.
This document provides information on various chemistry experiments and techniques. It discusses experiments on rates of reaction and factors that affect rates. Methods for separating mixtures like filtration, crystallization, distillation and chromatography are described. Tests for identifying cations and anions are outlined. Procedures for preparing and collecting gases in the laboratory are also summarized.
This document discusses iodine titrations, including iodimetric and iodometric titrations. Iodimetric titrations use iodine as the oxidizing agent, which reacts with strong reductants. Iodometric titrations involve liberating iodine from potassium iodide using an acid, then titrating the free iodine with sodium thiosulfate. Starch is commonly used as an indicator, turning blue when iodine is present. The document also provides procedures for preparing standard iodine and sodium thiosulfate solutions and describes how to standardize them using arsenic trioxide or potassium iodate, respectively.
This document discusses hydrates, which are compounds that have water molecules bound to their atoms. Hydrates can be named using the compound name followed by a dot and the number of water molecules. The water molecules can be removed through heating, changing the hydrate into its anhydrous form. To determine the formula of a hydrate, the moles of water lost upon heating are calculated and compared to the moles of the compound to obtain a molar ratio, which is used to derive the chemical formula. Examples are provided to demonstrate solving for the formula and name of hydrates. Finally, some common uses of hydrates as drying agents and in solar energy are mentioned.
Qualitative analysis of group 4 cationsJessa Ariño
This document analyzes group IV cations including barium, strontium, and calcium. It discusses how they form precipitates with carbonates in ammonium solutions and outlines their separation and identification processes. Barium, strontium, and calcium carbonates precipitate out of solution and can then be dissolved with acetic acid. Barium is identified through precipitation of barium chromate and barium sulfate. Strontium is identified by precipitation of strontium chromate which is yellow. Calcium is identified by precipitation of calcium oxalate which is white.
Alkalinity,hardness,softening BY Muhammad Fahad Ansari 12IEEM14fahadansari131
1. Lime-soda ash softening is used to remove calcium, magnesium, and non-carbonate hardness from water. Lime is added first to precipitate carbonates and hydroxides, then soda ash to remove non-carbonates.
2. Analyzing total hardness, calcium hardness, magnesium hardness, and alkalinity can help interpret which hardness forms are present and how much lime and soda ash are needed.
3. The process produces large volumes of sludge and leaves sodium in the treated water, but it is effective at lowering total dissolved solids and improving aesthetics by removing scale-causing ions.
Iodometry and iodimetry are titration methods that involve the reaction of iodine with an analyte. In iodometry, the analyte is an oxidizing agent that liberates iodine, which is then titrated with a standard thiosulfate solution. In iodimetry, the analyte is a reducing agent that is directly titrated with a standard iodine solution. Starch is commonly used as an indicator for the titrations. Iodometric and iodimetric titrations cannot be performed in strong acidic or basic conditions due to side reactions involving iodine and interference with the indicators. The methods are useful for determining concentrations of substances like vitamin C,
This document provides instructions for identifying cations through qualitative analysis using sodium hydroxide (NaOH) and ammonium hydroxide (NH3) solutions. Precipitates formed when salts are reacted with these reagents can indicate the present metal ions. Observations of solubility in excess reagent and reactions with other substances like hydrochloric acid help distinguish between ions. Proper technique like warming solutions gently and testing gas evolution with litmus paper is emphasized.
Sea water contains various dissolved ions that allow it to be used for industrial processes through electrolysis. Electrolysis of sea water involves passing electricity through it, breaking down water into hydrogen and oxygen gases and producing chlorine gas, hydrogen gas, and sodium hydroxide solution. The salt industry utilizes these products from sea water electrolysis in various ways, such as manufacturing chlorine for bleaches and hydrochloric acid for ammonia production.
THIS IS A PRESENTATION JUST THANKING THOSE WHO HAVE ALREADY LOOKED AT SOME OF MY PREVIOUS PRESENTATIONS. PLEASE LEAVE COMMENTS EXPLAINING ANY SUBJECTS THAT YOU WANT COVERING.
This document provides suggestions for career paths and ways to figure out what career suits you best. It recommends taking career quizzes on websites, speaking with friends and relatives about their careers, doing different types of work experience, considering favorite school subjects, and matching personality types to potential careers. The document aims to help readers who are unsure of their career path by exploring these options and sources of guidance.
This document discusses the reactions and properties of aliphatic alcohols. It outlines five main reactions: 1) replacement of hydrogen by sodium or other active metals to form alkoxides, with reactivity following 1o > 2o > 3o alcohols; 2) replacement of hydroxyl with halogen (Lucas test) with reactivity 3o > 2o > 1o alcohols; 3) oxidation to aldehydes and ketones using chromic acid or other oxidizing agents; 4) esterification with carboxylic acids to form esters; and 5) selective oxidation of methyl alcohol to formaldehyde using a copper catalyst.
Qualitative analysis of group 4 cationsJessa Arino
The Group IV cations are Ba2+, Sr2+, Ca2+.
These metals form chlorides, sulfides and hydroxides that are soluble under that prevail in the precipitations of Group I, II, and III.
Salt analysis involves identifying the cation and anion in an inorganic salt through a series of confirmatory tests. Tests are done by dissolving the salt in water and adding other substances to look for precipitates or color changes. For example, adding barium chloride to the water extract will form a white precipitate confirming the presence of a sulfate anion. Similarly, adding sodium hydroxide and Nessler's reagent can confirm the presence of an ammonium cation through the formation of a yellow or brown precipitate. The document then outlines the specific confirmatory tests used to identify 11 common cations and 12 common anions through characteristic reactions.
This document provides information on iodine titrations, including how they are used for both direct (iodimetry) and indirect (iodometry) titrations. It discusses the solubility of iodine, conditions and precautions for iodine titrations, various methods for determining the endpoint, and applications like assaying ascorbic acid, potassium permanganate, and other compounds. The document also describes how iodine solutions are standardized, often using sodium thiosulfate, as well as how sodium thiosulfate itself must be standardized due to its instability.
The document outlines methods for preparing specified salts through various chemical reactions. It discusses using precipitation reactions when salts are insoluble and acid-base reactions when salts contain sodium, ammonium, or potassium ions. The document provides examples of reacting acids with metal oxides, metals, and metal carbonates to produce salts. It also gives guidance on purification techniques like filtration, washing, drying, heating, cooling/crystallization after reactions. Finally, it includes 5 examples of stoichiometric calculations to determine moles, masses or volumes of reactants and products in salt forming reactions.
This document provides information on common cation and anion tests in chemistry. It lists several cations (aluminum, ammonium, calcium, copper, iron, zinc, lead) and their reactions when aqueous sodium hydroxide or ammonia is added. Precipitates formed are identified. It also lists several anions (carbonate, chloride, iodide, nitrate, sulfate) and their confirmatory chemical tests involving reactions like the formation of gases, precipitates with silver or barium salts, or color changes. The document serves as a reference for students to identify common metal cations and inorganic anions through characteristic chemical reactions.
Preparation of potash alum from aluminium scrapSwaroop Puhan
This document outlines the procedure for preparing potash alum from aluminum scrap. It begins with introducing the uses of alum and its chemical formula. The aim is to prepare potash alum (K2SO4.Al2(SO4)3.24H2O) from aluminum scrap through a series of chemical reactions. The required apparatus, theory, reactions, procedure, observations and conclusions are described in detail. Safety precautions are mentioned and references consulted are listed in the bibliography.
Analytical Procedures in Elemental Impuritiesumaiya fatima
This document discusses analytical procedures for determining elemental impurities like arsenic, lead, and mercury. It provides details on the methodology and reagents used for arsenic detection using the molybdenum blue method and atomic absorption spectrometry. For lead, the dithizone method is described where lead ions form a brown colloid with dithizone. Mercury detection uses the mercury(II) thiocyanate method where chloride ions displace thiocyanate and form a colored complex with iron(III). Spectrophotometric techniques are used for quantification and calibration curves.
This document provides an overview of qualitative inorganic analysis for identifying anions present in compounds. It discusses preliminary and confirmatory tests for several common anions including carbonate, nitrite, acetate, sulfide, sulfite, chloride, bromide, iodide, nitrate, and oxalate. Tests involve observing reactions, such as gas evolution or precipitate formation, when the sample is treated with acids or reagents. Positive test results are indicated by characteristic observations that confirm the presence of the suspected anion.
1. The document summarizes a lab report for a qualitative analysis experiment identifying inorganic compounds through precipitation reactions.
2. Key reactions identified calcium, copper, lead, carbonate, chloride, and sulfate ions based on the color and solubility of precipitates formed when the unknown compounds were reacted with specific reagents.
3. The experiment allowed the student to gain experience using common techniques to identify inorganic cations and anions through observation and interpretation of precipitation results.
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
Oxyacids of sulphur are sulphur, hydrogen and oxygen containing compounds. Oxyacids of sulphur are sulphurous acid, sulphuric acid, peroxomonsulphuric acid, peroxodisulphuric acid, thiosulphuric acid, dithionous acid, dithionic acid, polythionic acid and pyrosulphuric acid.
This document provides information on various chemistry experiments and techniques. It discusses experiments on rates of reaction and factors that affect rates. Methods for separating mixtures like filtration, crystallization, distillation and chromatography are described. Tests for identifying cations and anions are outlined. Procedures for preparing and collecting gases in the laboratory are also summarized.
This document discusses iodine titrations, including iodimetric and iodometric titrations. Iodimetric titrations use iodine as the oxidizing agent, which reacts with strong reductants. Iodometric titrations involve liberating iodine from potassium iodide using an acid, then titrating the free iodine with sodium thiosulfate. Starch is commonly used as an indicator, turning blue when iodine is present. The document also provides procedures for preparing standard iodine and sodium thiosulfate solutions and describes how to standardize them using arsenic trioxide or potassium iodate, respectively.
This document discusses hydrates, which are compounds that have water molecules bound to their atoms. Hydrates can be named using the compound name followed by a dot and the number of water molecules. The water molecules can be removed through heating, changing the hydrate into its anhydrous form. To determine the formula of a hydrate, the moles of water lost upon heating are calculated and compared to the moles of the compound to obtain a molar ratio, which is used to derive the chemical formula. Examples are provided to demonstrate solving for the formula and name of hydrates. Finally, some common uses of hydrates as drying agents and in solar energy are mentioned.
Qualitative analysis of group 4 cationsJessa Ariño
This document analyzes group IV cations including barium, strontium, and calcium. It discusses how they form precipitates with carbonates in ammonium solutions and outlines their separation and identification processes. Barium, strontium, and calcium carbonates precipitate out of solution and can then be dissolved with acetic acid. Barium is identified through precipitation of barium chromate and barium sulfate. Strontium is identified by precipitation of strontium chromate which is yellow. Calcium is identified by precipitation of calcium oxalate which is white.
Alkalinity,hardness,softening BY Muhammad Fahad Ansari 12IEEM14fahadansari131
1. Lime-soda ash softening is used to remove calcium, magnesium, and non-carbonate hardness from water. Lime is added first to precipitate carbonates and hydroxides, then soda ash to remove non-carbonates.
2. Analyzing total hardness, calcium hardness, magnesium hardness, and alkalinity can help interpret which hardness forms are present and how much lime and soda ash are needed.
3. The process produces large volumes of sludge and leaves sodium in the treated water, but it is effective at lowering total dissolved solids and improving aesthetics by removing scale-causing ions.
Iodometry and iodimetry are titration methods that involve the reaction of iodine with an analyte. In iodometry, the analyte is an oxidizing agent that liberates iodine, which is then titrated with a standard thiosulfate solution. In iodimetry, the analyte is a reducing agent that is directly titrated with a standard iodine solution. Starch is commonly used as an indicator for the titrations. Iodometric and iodimetric titrations cannot be performed in strong acidic or basic conditions due to side reactions involving iodine and interference with the indicators. The methods are useful for determining concentrations of substances like vitamin C,
This document provides instructions for identifying cations through qualitative analysis using sodium hydroxide (NaOH) and ammonium hydroxide (NH3) solutions. Precipitates formed when salts are reacted with these reagents can indicate the present metal ions. Observations of solubility in excess reagent and reactions with other substances like hydrochloric acid help distinguish between ions. Proper technique like warming solutions gently and testing gas evolution with litmus paper is emphasized.
Sea water contains various dissolved ions that allow it to be used for industrial processes through electrolysis. Electrolysis of sea water involves passing electricity through it, breaking down water into hydrogen and oxygen gases and producing chlorine gas, hydrogen gas, and sodium hydroxide solution. The salt industry utilizes these products from sea water electrolysis in various ways, such as manufacturing chlorine for bleaches and hydrochloric acid for ammonia production.
THIS IS A PRESENTATION JUST THANKING THOSE WHO HAVE ALREADY LOOKED AT SOME OF MY PREVIOUS PRESENTATIONS. PLEASE LEAVE COMMENTS EXPLAINING ANY SUBJECTS THAT YOU WANT COVERING.
This document provides suggestions for career paths and ways to figure out what career suits you best. It recommends taking career quizzes on websites, speaking with friends and relatives about their careers, doing different types of work experience, considering favorite school subjects, and matching personality types to potential careers. The document aims to help readers who are unsure of their career path by exploring these options and sources of guidance.
english language techniques, explains teaches and gives evidence on some of the most important language devices. Also it shows you the different levels of punctuation followed by explaining what each of them mean and giving examples of how to apply them.
How to craete your own background on PowerPointBeth A
This document provides instructions for creating a gradient background on PowerPoint similar to the author's. It involves right clicking the format background option, selecting gradient fill, then choosing colors for gradient stops 1 through 3. Users should then follow diagrams to select the radial gradient option and apply it to all slides before closing.
This document provides instructions and examples for using onomatopoeia, which are words that imitate sounds. It explains that onomatopoeia adds emphasis and engages readers. Examples include crash, bang, and pop. Readers are asked to fill in missing letters and create their own onomatopoeic words. An example sentence describes a fall with an "almighty CRASH!" The document quizzes readers on rules for using onomatopoeia and checks their understanding.
This document discusses biological classification and the binomial system of naming species. It explains that there are five kingdoms that organisms are divided into based on their cell structure. It then describes the levels of classification from kingdom down to species. Key terms like vertebrate, invertebrate, oviparous and viviparous are defined in relation to different groups of animals. The importance of the binomial system of naming species using genus and species is also outlined.
Acids, bases and salts according to the syllabus of CAIE and IGCSEjaveriakhan123
This document provides information about acids and bases:
- Acids are substances that produce hydrogen ions in water and have properties like a sour taste and turning litmus paper red. Strong acids fully ionize in water while weak acids only partially ionize.
- Bases include metal oxides and hydroxides. Soluble bases are called alkalis. Bases react with acids to produce salt and water in a neutralization reaction.
- Important acids and bases have many applications from batteries to cleaning to food preservation. Processes like the Contact Process are used industrially to produce acids like sulfuric acid.
This document describes various chemical tests to identify cations, anions, and gases. It outlines the procedure and expected results for tests to identify aqueous cations such as aluminum, ammonium, calcium, and iron using sodium hydroxide and ammonia solutions. It also describes flame tests to detect lithium, sodium, potassium, and copper cations. Further, the document details how to identify carbonate, halide, nitrate, sulfate, and sulfite anions through reactions involving acids, gases, and reagents like silver nitrate and barium chloride. Finally, it lists procedures to recognize ammonia, carbon dioxide, chlorine, hydrogen, oxygen, and sulfur dioxide gases using indicators like litmus paper and limewater
1. Salts can be either soluble or insoluble depending on their constituent ions. Soluble salts dissolve in water while insoluble salts do not.
2. Insoluble salts are prepared through precipitation or double decomposition reactions between aqueous solutions containing the ions that will form the insoluble salt. Soluble salts are prepared through acid-base reactions or reactions between acids and reactive metals/metal oxides/carbonates.
3. Both soluble and insoluble salts require purification steps like filtration, rinsing, and drying to obtain the pure salt.
The document provides information about various chemistry concepts related to air and water:
- It describes chemical tests to identify water and the purification of water supplies through filtration and chlorination.
- The composition of clean air is described as 78% nitrogen, 21% oxygen and small quantities of other gases. Common air pollutants like carbon monoxide and their sources are stated.
- Fractional distillation is outlined as the process used to separate oxygen and nitrogen from liquid air based on their different boiling points.
- Rusting is described as a reaction between iron, air and water that can be prevented by methods like painting and galvanizing to exclude oxygen.
This document discusses different types of metal oxides and methods for preparing soluble salts. It describes basic oxides, amphoteric oxides, and acidic oxides. It also outlines soluble and insoluble salts. Three methods are provided for preparing soluble salts: the displacement method using reactive metals, the neutralization method between an acid and base, and the titration method. The precipitation method is described for making insoluble salts. Key steps and observations are highlighted for correctly carrying out these preparation reactions.
This document provides a 22 question practice exam on the preparation of salts from acids and bases/metal oxides/carbonates. It tests understanding of the key steps in salt preparation including addition of excess reactant, filtration, evaporation and crystallization. Questions cover the preparation of specific salts such as copper(II) sulfate, magnesium sulfate and ammonium sulfate.
1. The document is a 17-page syllabus approved for use in England, Wales and Northern Ireland as a Cambridge International exam.
2. It includes blank pages and an identification code.
3. The document provides information and instructions for an exam.
Diamond has a giant covalent structure where each carbon atom is bonded to four other carbons, giving it properties like hardness and electrical insulation. It is used in cutting, jewelry due to its brilliance, and lasers. Graphite has layers of hexagonal carbon sheets bonded by van der Waals forces, making it soft and a conductor. It is used as a lubricant, in electrodes, and pencils. Hard water contains calcium and magnesium ions that form precipitates with soap. Temporary hardness can be removed by boiling or adding washing soda while permanent hardness requires ion exchange or distillation. Carbon forms oxides, is a reducing agent, and is important in combustion, fermentation, and the carbon cycle.
The early atmosphere on Earth was formed by gases released from volcanic eruptions. The main gases were carbon dioxide, nitrogen, water vapor, and ammonia, with little to no oxygen. Over time, carbon dioxide levels fell as it dissolved in the oceans and was incorporated into marine organisms' shells. As plant life increased through photosynthesis, oxygen levels rose and carbon dioxide levels fell further. Rocks can provide information about the early atmosphere by analyzing their mineral composition and looking for oxide formations that indicate higher oxygen levels over time.
This document provides information about water technology and water treatment. It discusses the existence and states of water on Earth, sources of water including surface and underground sources, types of water impurities and their effects, hardness of water, types of hardness and units of measurement, disadvantages of hard water, estimation of hardness, scale and sludge formation in boilers, and methods of water treatment both internal and external methods. It covers topics like ion exchange process, zeolite process, desalination methods like electrodialysis and reverse osmosis.
This document provides a chemistry exam on acids, bases and salts from the Cambridge International Examinations board. It contains 21 multiple choice questions testing understanding of concepts such as the preparation of salts from reactions between acids and bases or metal oxides. Students are asked about the purpose of steps in salt preparation procedures, the products and reagents of different salt forming reactions, and the equipment used. The document also provides the grade boundaries for the exam.
This document describes the double decomposition method for forming insoluble salts. It involves mixing two aqueous solutions containing different metal ions that exchange to form an insoluble salt precipitate. Specifically, it provides the example of mixing lead (II) nitrate and potassium iodide solutions to form lead (I) iodide precipitate. The procedure involves mixing the solutions, filtering out the precipitate, washing it with water, and drying to obtain pure salt crystals.
Preparation of salts (multiple choice) qpRubaHusain
Step 3 is to ensure all of the acid has reacted by adding copper(II) oxide in excess. Step 4 is to remove any excess copper(II) oxide by filtration to obtain pure copper(II) sulfate crystals.
The correct sequence of steps is: dissolving → filtration → evaporation → crystallisation.
Salts can be prepared by reacting dilute acids with metals, bases, or carbonates. Copper(II) chloride could be prepared by reacting copper with hydrochloric acid or by reacting copper carbonate with hydrochloric acid.
This document describes the precipitation method for determining the chloride ion concentration of a solution by titration with silver nitrate. Silver nitrate is added until all chloride ions are precipitated as silver chloride. Additional silver ions then react with potassium chromate indicator to form a red-brown silver chromate precipitate, signaling the endpoint. The method can be used to analyze water samples. It involves titrating aliquots of the sample with a standardized silver nitrate solution until concordant results are obtained.
Sodium, magnesium, and aluminium react with oxygen to form ionic oxides. Sodium oxide and magnesium oxide are basic due to their oxide ions and react with water to form alkaline solutions. Aluminium oxide is amphoteric as it displays both acidic and basic properties, reacting with both acids and bases. Silicon dioxide does not react with water or acids due to its covalent bonding. Phosphorus and sulphur form acidic oxides that react with water to produce acids. Chlorine forms oxides that react with water to form acids or salts.
This document provides information about water treatment processes and ion exchange resins used in water purification. It discusses the sources and types of water impurities and how treatment methods like coagulation with polyaluminum chloride, filtration through activated carbon filters, and ion exchange with resins like strong acid cation and weak acid cation can remove various contaminants. It also provides specifications for the ion exchange resins and details their chemical properties and manufacturing processes.
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
1) Copper was one of the first metals isolated due to its ease of separation from ores as early as 4500 BC.
2) This experiment transforms copper metal through a series of reactions including metathesis, decomposition, displacement, and oxidation-reduction into copper compounds and back to copper metal.
3) The series of reactions begins and ends with copper metal and involves the use of nitric acid, sodium hydroxide, sulfuric acid, and zinc.
This document discusses water resources, water purification processes, and water quality testing. It describes various water sources like lakes, rivers, and aquifers. It explains how water is used in industry for cooling, solvents, and as a raw material. It also lists common pollutants in water sources like nitrates, lead, and pesticides. The purification process removes insoluble solids through sedimentation, filters out smaller particles, and uses chlorination to kill microbes. Testing identifies ions that cause water hardness and determines which halide ions are present through precipitation reactions.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxEduSkills OECD
Iván Bornacelly, Policy Analyst at the OECD Centre for Skills, OECD, presents at the webinar 'Tackling job market gaps with a skills-first approach' on 12 June 2024
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
-------------------------------------------------------------------------------
Find out more about ISO training and certification services
Training: ISO/IEC 27001 Information Security Management System - EN | PECB
ISO/IEC 42001 Artificial Intelligence Management System - EN | PECB
General Data Protection Regulation (GDPR) - Training Courses - EN | PECB
Webinars: https://pecb.com/webinars
Article: https://pecb.com/article
-------------------------------------------------------------------------------
For more information about PECB:
Website: https://pecb.com/
LinkedIn: https://www.linkedin.com/company/pecb/
Facebook: https://www.facebook.com/PECBInternational/
Slideshare: http://www.slideshare.net/PECBCERTIFICATION
2. Topic 1 – Qualitative Analysis
■ Demonstrate an understanding that analysis may be qualitative or quantitative.
■ Explain why the test for any ion must be unique.
■ Purity of drinking water.
■ Describe tests to show:
– Aluminium,Calcium,Copper, Iron (II) and Iron (III)
– Ammonium plus sodium hydroxide solution
– Cl, Br, I using dilute nitric acid and silver nitrate solution.
3. WaterTesting
■ Qualitative: Investigation into what kind of substances are present.
■ Quantitative: Investigation into the amount of substances that are present.
■ Flame tests are qualitative:
– If 2 metal ions produce a similar colour, you could get
the wrong identification.
– So, you can add acid and silver nitrate, which
forms a precipitate.This can identify some anions
in a more clear way.
FlameTest recap:
Potassium – lilac
Calcium – brick red
Copper – green
Sodium - yellow
4. Testing for Cations using Sodium
Hydroxide:
Cation Symbol Effect of adding Sodium
Hydroxide
Name of precipitate
formed
Aluminium Al³+ Precipitate formed
Cloudy (white) (limewater)
Aluminium Hydroxide
Calcium Ca²+ Precipitate formed
Cloudy (white)
Calcium Hydroxide
Copper Cu²+ Pale blue precipitate
formed
Copper Hydroxide
Iron (II) Fe²+ Green precipitate Iron Hydroxide
Iron (III) Fe³+ Precipitate formed
Cloudy (brown(rust))
Iron Hydroxide
Copper sulfate + sodium hydroxide → copper hydroxide + sodium sulfate
CuSO4 + 2NaOH → Cu(OH)2 +Na2SO4
5. Qualitative tests are carried out before
quantitative tests
■ 1) If the precipitate formed is brown, the ion present is _______________
■ 2) If the precipitate formed is white, the ion could be ______ or _______
■ 3)The level of salt in food is: quantitative or qualitative?
■ 4)The source of pollution in a river is: quantitative or qualitative?
■ 5) aluminium sulfate + sodium hydroxide → __________ + ____________
6. Qualitative tests are carried out before
quantitative tests
■ 1) If the precipitate formed is brown, the ion present is Iron (III)
■ 2) If the precipitate formed is white, the ion could be Calcium or Aluminium
■ 3)The level of salt in food is: quantitative or qualitative?
■ 4)The source of pollution in a river is: quantitative or qualitative?
■ 5) aluminium sulfate + sodium hydroxide → aluminium hydroxide + sodium sulfate
7. Effects of drinking sea water
Drinking Sea
Water
Blood
pressure and
heart rate
increases
Physiological
changes eg)
headaches
Kidney failure
dehydration
Brain
damage
Excessive
thirst
8. Halide (the negative ion formed by a
halogen atom)
Halide Ion Effect of adding acidified silver
nitrate solution
Chloride Cl- White coloured precipitate
Bromide Br- Cream/grey precipitate
Iodide I- Green/yellow precipitate
9. Method to test for Halide ions:
■ Carefully, pour 1cm³ of each halide into 3 separate test tubes (chloride, bromide,
iodide).
■ Add a few drops of acidified silver nitrate solution until a precipitate begins to form.
■ Shake and allow to settle.
■ Record results.
12. Testing for ammonium ions
Observations after warming with sodium hydroxide
solution.
Smell Effect on moist red litmus
paper.
A Ammonia → pungent Blue/purple
B No smell No change
C Ammonia → pungent Blue/purple
D Ammonia → pungent Blue/purple
Therefore, Fertiliser B is not an ammonium ion.
13. Method to test for ammonium ions:
■ Pour each pre-made fertilisers into 4 separate test tubes and label A, B, C, D.
■ Add 1cm³ of sodium hydroxide solution and shake.
■ Using test tube clamps, hold over a Bunsen burner.
■ As soon as it begins to bubble, pour into a beaker and smell it. If it smells of ammonia
(a hair dye smell) then hold moist red litmus paper over the beaker, it should turn
blue/purple
■ Record results.
14. ■ To practice this, find a sheet based on Ions in our water and writing chemical equations
(C3.2d sheet and C3.4b sheet).
15. Water solutes
■ Hard water = high in dissolved minerals, specifically calcium and magnesium ions. It
doesn’t lather easily with soap.
■ Soft water = is treated water in which the only cation (+) is sodium and forms a good
lather with soap.
16. Hard water
Hard water
makes scum
• Reacts with soap to
make a nasty precipitate
called scum.
• Hard water is caused by
Ca²+ and Mg²+ ions.
Magnesium
sulfate (MgSO4)
dissolves in
water.
• So does calcium sulfate
Calcium
carbonate
• Calcium carbonate exists as
chalk, limestone or marble.
• It can react with acid rain to
form hydrogencarbonate
Ca(HCO3)2.
• It is soluble in water and
releases Ca²+.
17. My results
Sample Amount of soap needed
Distilled 5ml Softer
A 20% 13ml
B 60% 20ml
C 100% 25ml
D 140% 30ml Harder
18. Method to test hard/soft water
■ Measure 25cm³ of a sampled concentration of water into a boiling tube or conical flask.
■ Pour 5ml of the soap solution into the flask or boiling tube using a pipette.
■ Fit a bung and shake well
■ Allow to settle
■ If a lather has not formed, add another 5ml of soap solution and repeat until a lather forms.
■ Record the amount of soap solution needed.
■ To conclude, the pure water forms a lather easier because it is softer and doesn’t contain
magnesium or calcium ions.Whereas, the 140% concentrated sample was harder to form a
lather as it contained more magnesium and calcium ions.
19. calculations
■ M = mass of solute (g)
■ C = concentration (g dm-3)
■ V = volume (dm3)
■ 1 dm3 = 1 litre = 1000cm3
– Eg) 250cm3 = 0.25dm3
– Eg) 50mg = 0.05g
20. Worked example
■ What mass of sodium chloride is in 300cm3 of solution with a concentration of 12gdm-3?
– 300cm3 = 0.3dm3
– M = c x v
– 0.3 x 12 = 3.6g
■ There are 0.4g of calcium ions dissolved in 2 litres of water.What is the concentration?
– C = m ÷ v
– C = 0.4 ÷ 2
– C = 0.2 gdm-3
21. Hard and soft water
■ Magnesium ions and calcium ions make up hard water.
– They react with the stearate in the soap.
■ What are the problems with hard water?
22. Temporary hardness
■ Temporary hardness = property of hard water that can be removed by boiling the
water.
■ So, this is a thermal decomposition reaction forming insoluble calcium carbonate
which forms a limescale precipitate.
■ Permanent hard water = property of hard water that cannot be removed by boiling
the water.
– has no dissolved hydrogencarbonate ions to decompose – so when it is heated there
is no change and the water stays hard.
– Permanent water contains Ca and Mg chlorides and/or sulfates, which become more
soluble as the temperature increases.
23. Method to test how temporary and
permanent hard water are affected by heat
■ Put 25cm3 of temporary hard water into a boiling tube and label A1.
■ Put 25cm3 of temporary hard water into a boiling tube and label B1.
■ Put 25cm3 of permanent hard water into a boiling tube and label A2.
■ Put 25cm3 of permanent hard water into a boiling tube and label B2.
■ Add soap to both A’s and shake.
■ Heat both B’s, cool, then add soap and shake.
■ Record results.
24. Ion exchange column
■ Both types of hard water can be softened by passing them through an ion exchange
column.
■ This swaps the calcium ions and magnesium ions in the water for sodium ions.
■ Sodium ions do not cause hardness in water.
■ An ion exchange column is packed with tiny plastic beads made of ‘resin’ (polymer).
■ When hard water is passed through the column, positively charged Ca and Mg ions in
the water swap with positively charged Na ions which are weakly attached to the
resin.
■ The swap of ions makes the water softer.
30. 5) Positive ions
■ Add a few drops of sodium hydroxide solution to your mystery compound.
■ Calcium – white precipitate
■ Copper – blue precipitate
■ Iron (II) – green precipitate
■ Iron (III) – brown precipitate
■ Aluminium – white precipitate at first but then it re-dissolves to form a colourless
solution.
32. Particles and moles
■ Diamond is made up of carbon atoms. How much diamond is there?
– How many carbon atoms are there in 12g of Diamond?
– 6.02x10^23
– How do we know??!!
33. Avogadro’s number
■ The amount of a substance can be measured in grams, number of particles, or number
of moles.
■ The mass of an element equal to its atomic mass in grams always contain 6.02x10^23
atoms.
■ This is Avogadro’s number.
35. Your turn
■ How many atoms are there in 32g of sulphur?
■ = sulphur = mass number = 32
■ Therefore the mass and the mass number is equal so avogadros number is the answer!
■ 6.02x10^23
36. Particles and moles
■ Mole = the quantity of a substance which is equivalent to its relative atomic/formula
mass in grams.
■ Eg) RFM (Mr) of water is 18 (H2O = 1+1+16).
– 18g of water contains an Avogadro’s number of water molecules, so 1 mole of water
has a mass of 18g.
37. Which of these contains 1 mole of
particles?
■ 8g of oxygen
■ 20g of magnesium
■ 44g of carbon dioxide
■ 40g of potassium
38. Which of these contains 1 mole of
particles?
■ 8g of oxygen
– 0=16 (6.02x10^23) ÷ 2 = 3.01x10^23 = 0.5M
■ 20g of magnesium
– Mg=24 20g=0.83M
■ 44g of carbon dioxide
– CO2=44 44=44=1M
■ 40g of potassium
– K=39 39 ÷ 40 = 0.975M
39. Calculation
■ How many moles are there in 88g of CO2?
– CO2 = 44g = 1M 88g = 2M
■ How much mass is there in 162M of water?
– H2O = 18 18x162 = 2916g
■ How many moles are there in 80g of calcium?
– Ca = 40 = 2M
41. Your turn
■ Seawater contains 30g of NaCl in every 1dm3. calculate the concentration.
42. Your turn
■ Seawater contains 30g of NaCl in every 1dm3. calculate the concentration.
■ 30 ÷ 58.5 = 0.512820mdm3
43. Preparing soluble salts
■ If soluble salts are prepared from an acid and an insoluble reactant:
– Excess of the reactant can be added to ensure that all the acid is used up.
– The excess reactant can be removed by filtration.
– The remaining solution is only salt and water.
Sodium hydroxide + hydrochloric acid → sodium chloride + water
Copper oxide + hydrochloric acid → copper chloride + water
= neutralisation
44. Making copper sulfate (CuSo4)
■ Copper oxide + hydrochloric acid → copper chloride + water
■ =a soluble salt made form an insoluble base.
■ 1) pour 20cm3 of sulphuric acid into a beaker.
■ 2) warm over Bunsen burner whilst adding excess copper oxide to the solution.
■ 3) remove from heat and pour into a filter over an evaporating dish.
■ 4) it should drip out as a blue solution.
■ 5) heat the evaporating dish until the liquid boils.
■ 6) leave to cool.
45. Experiment explanation
■ You know the reaction took place because it changed colour (black to blue).
■ You don’t know that the reaction was ever complete, though,
■ The acid was warmed to catalyse the experiment.
■ CuO (s) + H2SO4 (aq) → CuSO4 (aq) + H2O (aq)
46. Titrations
■ Titrations are used to find out concentrations.
■ An acid-based titration is a neutralisation reaction where Hydrogen ions from an acid
react with hydroxide ions from a soluble base (alkali).
■ H+ + OH- → H2O
■ Titrations allow you to find out exactly how much acid is needed to neutralise a
quantity of alkali (or vise versa).
47. Method
■ 1) add 25cm3 of alkali to a conical flask, along with 2 or 3 drops of indicator.
■ 2) the indicator used depends on the strengths of the acid and alkali:
– Phenolphthalein = used for a weak acid + a strong alkali.
– Methyl orange = used for a strong acid + a weak alkali.
– If both the acid and the alkali are strong, then any acid based indicator can be used.
■ 3) fill a burette with acid, below eye level.
■ 4) using a burette, add the acid to the alkali a small amount at a time – giving the conical
flask a regular swirl.Go slowly when you think the end-point (colour change) is about to be
reached.
■ 5) the indicator changes colour when all the alkali has been neutralised.
– Eg) phenolphthalein is pink in alkalis, but colourless in acids.
■ 6) record the volume of acid used to neutralise the alkali.
49. Titration step-by-step calculations.
■ 25cm3 of NaOH solution was titrated against 0.1Moldm-3 HCL.An average of 20cm3
of the acid was needed to react completely.What is the concentration of the NaOH
solution?
50. Titration step-by-step calculations.
■ 25cm3 of NaOH solution was titrated against 0.1Moldm-3 HCL.An average of 20cm3
of the acid was needed to react completely.What is the concentration of the NaOH
solution?
■ Step 1: Number of moles of HCL acid = concentration of HCL xVolume used
– Number of moles of HCL acid = 0.1 x (20÷100) = 0.002mol
51. Titration step-by-step calculations.
■ 25cm3 of NaOH solution was titrated against 0.1Moldm-3 HCL.An average of 20cm3
of the acid was needed to react completely.What is the concentration of the NaOH
solution?
■ Step 1: Number of moles of HCL acid = concentration of HCL xVolume used
– Number of moles of HCL acid = 0.1 x (20÷100) = 0.002mol
■ Step 2: write the balanced equation:
– NaOH + HCL → NaCl + H2O
– The equation shows that the ratio of NaOH : HCL is 1:1 so the moles are equal.
– Therefore, 0.002:0.002 moles.
52. Titration step-by-step calculations.
■ 25cm3 of NaOH solution was titrated against 0.1Moldm-3 HCL. An average of 20cm3 of the
acid was needed to react completely. What is the concentration of the NaOH solution?
■ Step 1: Number of moles of HCL acid = concentration of HCL xVolume used
– Number of moles of HCL acid = 0.1 x (20÷100) = 0.002mol
■ Step 2: write the balanced equation:
– NaOH + HCL → NaCl + H2O
– The equation shows that the artio of NaOH : HCL is 1:1 so the moles are equal.
– Therefore, 0.002:0.002 moles.
■ Step 3: concentration of NaOH = moles of NaOH ÷ volume of NaOH
– Concentartion of NaOH = 0.002 ÷ (25÷1000)
– Concentration of NaOH = 0.002 ÷ 0.025 = 0.08moldm-3
53. Electrolysis
■ 1) electricity comes from a battery, providing a direct current.
■ 2) It requires a liquid to conduct electricity (an electrolyte).
■ 3) the electricity is applied by two electrodes.
■ 4) this breaks down the compound into its component parts (often as a gas).
■ O – Oxidation
■ I – Is
■ L – loss of electron
■ R – reduction
■ I – is
■ G – gain of electron
54. Making ions move with electrolysis
(this method is only for coloured ions)
■ 1) connect a DC supply to a slide and filter paper.
■ 2) put a crystal on the top of the filter paper and slide and add water (drops).
■ 3) the solution should be drawn towards the negative (cathode) to prove it’s a positive
ion.
57. Practice these: (normally to ½
equations)
■ 1) 2LiI → Li + I2
– Li + e- → Li (cathode)
– 2I → I2 + 2e- (anode)
58. Electrolysis of salts
Observations Anode (+) Cathide (-) Solution left
Sodium sulfate Bubbles at both
electrodes
O2- H2+ Sodium sulfate
Sodium chloride Fizzing, bubbling,
clouding
Cl2- H2+ Sodium hydroxide
Copper chloride Bubbles and visible
copper
Cl2- Cu2+ Water
Copper sulfate Copper at cathode,
bubbles at anode,
pieces of visible
metal.
O2- Cu2+ Sulphuric acid
59. Rule
■ At the cathode: Always Hydrogen will be formed, unless the metal is less reactive
than hydrogen.
■ At the anode:Always Oxygen unless a halide is present.
60. Electroplating
■ Electrolyte = solution you are breaking down in electrolysis or electroplating.
■ Electroplating = covering one metal with a thin layer of another metal, using
electrolysis.
■ Anion = -
■ Cation = +
■ Anode = +
■ Cathode = -
■ Cathode (-) attract cations (+).
61. Electroplating has many uses:
■ Jewellery and decorative items:
– With metals like gold and silver.
– Improves appearance.
■ Cooking utensils and cutlery:
– Stop them corroding.
– With unreactive metals which don’t corrode easily (eg nickel or chromium).
■ Electrolysis = 2 products
■ Electroplating = one product transferred to the cathode.
62. Copper extraction
■ 2CuCO3 → 2Cu + 3CO2
■ Why is copper important to us?
– Used In pipes , electrical generators and motors.
■ Industrial extraction of copper (smelting):
– Copper-rich ores →
– Cooper can be extracted from these ores using heat
in a furnace →
– This is smelting→
– Cooper then purified using electrolysis.
■ Purification of copper using electrolysis:
– -------------------------------------------------------------------
63. ■ Ore = a naturally occurring solid material from which a metal or valuable mineral
can be extracted profitably.
■ Extraction = separation of a compound.
■ Impure = containing more than one material other than the intended pure material.
■ Smelting = an extraction method using heat, usually also resulting in oxidation.
65. Molar volume of gas
■ Another Avogadro’s law = one mole of any gas occupies 24dm3.
■ 1 mole at any gas at room temperature (25°) and normal atmospheric pressure (1
atmosphere), has a volume of 24dm3.
■ Vol of gas = (mass of gas ÷ Mr of gas) x 24
66. Reversible/irreversible reactions
■ Reactants → products = irreversible.
■ Reactants products = forwards reversible
■ Products reactants = backwards reversible
■ Reversible reaction = a chemical recation that can work in both directions.
67. Industrial manufacture of ammonia
■ Pressure = 200 atmosphere
■ Temperature = 450°C
■ Catalyst = iron.
■ Ammonia is used to make nitrogenous fertilisers.
■ N2 + 3H2 2NH3
■ N2 = from the air and 3H2 = from natural gases.
■ Not all the nitrogen and hydrogen will convert to ammonia.The reaction reaches a dynamic
equilibrium.
■ 1) air liquefied under pressure
– Optimum temp = 450°C = forwards reaction
– Optimum pressure = 200 atmospheres = forward reaction
– Iron catalyst
– Exothermic reaction = heat produced.
■ Increasing the temperature will speed up the rate of reaction, making it turn into a backwards
reaction which they don’t want, so they must be accurate with not surpassing or exceeding the
temperature too much.
68. Ammonia
■ Cleaning
■ Very strong alkali
■ Explosives
■ 85% used for nitrogenous fertilisers
■ Can cause eutrophication.
69. Dynamic equilibrium
■ = the reactions are taking place in both directions at exactly the same rate, so there is
no overall affect.
■ This occurs in a closed system, where no reactants or products can escape.
■ Forwards = exothermic = releases heat
■ Backwards = endothermic = takes in heat.
■ Catalysts = decrease the activation energy.
70. Le Chantelier’s Principle
■ Rule = any change made to a reaction which is in equilibrium, will result in the
equilibrium position moving to minimise the change made.
■ Exothermic
– High temp = backwards
– Low temp = forwards
■ Endothermic
– High temp = forwards
– Low temp = backwards
■ Same for pressure
71. Questions
■ Define the dynamic equilibrium.
■ What will a higher pressure do to the equilibrium yield of ammonia?
■ What would a lower temperature do to the equilibrium yield?
■ What is a catalyst used for?
■ What is the minimum volume of Hydrogen required to convert 1000dm3 of nitrogen
into ammonia?
72. Questions
■ Define the dynamic equilibrium.
– = rate of reactions in both direction occur at exactly the same rate.
■ What will a higher pressure do to the equilibrium yield of ammonia?
– = increase the yield of ammonia.
■ What would a lower temperature do to the equilibrium yield?
– = Increase the equilibrium yield.
■ What is a catalyst used for?
– = to increase the rate of reaction.
■ What is the minimum volume of Hydrogen required to convert 1000dm3 of nitrogen into
ammonia?
– N2 + 3H2 → 2NH3
– 1 : 3
– 1000 x 3 = 3000dm3.
73. Alcoholic drinks and ethanol production
■ 1 unit = 10cm3 of pure ethanol.
– Average amount that can be processed in one hour.
■ Ethanol catalyst ethene + steam.
Making ethanol
From ethane
(cracking crude oil)
Fermentation with
yeast
74. Fermentation with yeast
■ Sugar yeast ethanol + carbon dioxide
■ Yeast contains enzymes which convert sugar to ethanol.
■ The optimum temperature is 37°C because Zymase works best at this temperature (if it is
too hot the enzyme will denature, but if too cold the reaction will be too slow.
■ The optimum pH is pH 4 as Zymase likes slightly acidic conditions.
■ No oxygen should enter the reaction, as this converts ethanol to vinegar (ethanoic acid).
■ When a concentration of 10-15% is reached, the fermentation stops because the enzyme
becomes denatured by the ethanol.
■ This process is too slow for large-scale production.
■ Ethanol boils at a lower temperature than water = fractional distillation.
75. Hydration of ethene
■ Ethene reacts with steam to make ethanol by hydration (adding water)>
■ C2H4 + H2O → C2H5OH
■ Optimum temperature = 350°C
■ Optimum pressure = 60-70 atmospheres
■ Catalyst = phosphoric acid (HPO3).
C = C
H
C
HH
H
76. Adv. / Disadv.
Advantage Disadvantage
Fermentation Uses a renewable source. The quality of the ethanol
produced isn’t a high
standard.
Its expensive to concentrate
and purify.
Less space for farming.
Takes a long time.
Ethene 100% pure.
Little/no waste products.
Quick, continuous, cheap.
Crude oil is non-renewable.
High energy costs to maintain
high temperature and
pressure.
77. Homologous series
■ A group of similar compounds (with the same general formula and similar properties,
but have different number of carbon atoms). Eg) alkanes, alkenes and alcohols.
(alkane = CnH2n+2 alkene = CnH2n alcohols = CnH2n+OH)
■ Methane = one carbon atom
■ Ethane = two carbon atoms.
■ Propane = three carbon atoms.
■ Alcohols have an ‘-OH’ functional group and end in ‘-ol’.
– Eg) methanol
– Eg) ethanol
– Eg) propanol.
78. Functional groups
■ =the reactive part of the molecule.
■ In alcohols it is the –OH group (hydroxyl group).The rest of the hydrocarbon chain is
saturated and hence unreactive.
■ Methanol = CH3OH
■ Ethanol = C2H5OH ------------------------------------------------ =
O - H - C – C - H
H
H H
H
79. Alcohol
■ Alcohols combust with oxygen to produce carbon dioxide and water.
■ Alcohol is flammable, good fuels and have a clearer flame than hydrocarbons.
liquid methanol Ethanol Propanol hexane
No. of carbon atoms. 1 2 3 6
Test 1: mixing with
water.
Mixed. Pretty mixed. Most mixed but if left
will separate to two
layers.
Two layers.
Test 2: how does it
burn?
Orange flame.
Easily.
Blue ish flame Blue flame, burns
very well.
Extremely easily
ignited. But doesn’t
last as long.Orange
flame.
Test 3: reaction with
sodium.
Fizzing Fizzing fizzing
80. Ethanoic acid
■ = in vinegar.
■ If wine or beer is left open, the ethanol is oxidised to ethanoic acid.
■ Ethanol + oxygen → vinegar + water
■ C2H5OH + O2 → CH3COOH +H2O
■ This reaction is also used for the commercial production of vinegar.
■ Vinegar can be used for flavouring and the preservation of food.
81. Carboxylic acids
■ They are weak acids that have a –COOH- functional group (carboxyl) and end in –anoic acid- .
■ Carboxylic acid formula = CnH2nO2.
■ Vinegar:
– Ethanol oxidises into ethanoic acid.
– Due to bacteria in an aerobic process, unlike ethanol production which is anaerobic.
– Processes up to 15% takes 24 hours.
– Used to preserve food ‘pickling’ because bacteria cant live In the acidic conditions.
– We pickle savoury but not sweet, we usually use jam for sweet food.
– Ethanol + oxygen → ethanoic acid + water
– C2H5OH + O2 → CH3COOH +H2O H - C – C – O - H
H
H II
O
= Ethanoic acid
CH3COOH
vinegar
82. Properties of carboxylic acids
■ A) testing ethanoic acid with universal indicator
– = it turns red.
■ B) observations when heated
– = the copper oxide formed a blue salt solution.
■ C) Adding magnesium
– = hydrogen gas is given off
– = fizzing and bubbles
■ D) adding sodium hydrogencarbonate
– = carbon dioxide produced
– = Fizzing and bubbles and turned limewater cloudy.
83. Reactions
■ Reaction with a metal
– Ethanoic acid + magnesium → hydrogen + magnesium ethanoate
– 2CH3COOH + Mg → H2 + (CH3COO)2Mg
– = a salt
■ Reaction with a base
– Ethanoic acid + sodium hydroxide → sodium ethanoate + water
– CH3COOH + NaOH → (CH3COO)Na + H2O
■ Reaction with a carbonate
■ Ethanoic acid + sodium carbonate → sodium ethanoate + carbon dioxide + water
■ CH3COOH + NaCO3 → (CH3COO)2Na + CO2 + H2O
84. Esters
■ Have the functional group –COO- and end in –yl…-oate.
■ Theyre formed when an alcohol reacts with a carboxylic acid.
■ They have sweet and fruity smell and comes in many flavourings and perfumes eg)
peardrops.
■ They are volatile.
■ They are made from an esterification reaction:
– Alcohol + carboxylic acid ester + water
85. H - C – C – O - H
H
H II
O
H – O - C – C - H
H
H H
H
H - C – C
H
H II
O
O - C – C - H
H
H H
H
+ H2O
H - C – C
H
H II
O
- O - C – C - H
H
H H
H
+ H2O
Ethanoic acid Ethanol
Ethyl ethanoate
87. Questions
■ 1) ethanol + ethanoic acid ethyl ethanoate + ?
■ 2) propanol + ethanoic ? ? + water
■ 3) Butanol + ?? Butyl ethanoate + water
■ 4) ? + propanoic acid Ethyl ? + water
■ 1) water
■ 2) acid and propyl ethanoate
■ 3) ethanoic acid
■ 4) ethanol and propanoate
88. method
■ 250cm3 of boiling water into a beaker.
■ Put 2cm of ethanol into a test tube.
■ Get a pre-prepared test tube of 1cm3 concentrated sulphuric acid.
■ Mix the two test tubes together. Stand the test tube in the hot water beaker for 5
mins.
■ collect 50cm3 sodium hydrogencarbonate into a beaker.
■ Tip the test tube into the hydrogencarbonate and stir.
■ smell.And record results.
■
89. polyesters
■ = polymers made form 2 types of monomer:
– A carboxyl group ( from a carboxylic acid)
– A hydroxyl group ( from an alcohol).
■ Polyesters can be made into long, thin fibres which can be woven together to make
fabrics or drinks bottles.
■ Drinks bottles can be recycled to make fleece, which can be used to make clothing.
90. Name Formula Structure of a molecule
Methanoic acid HCOOH DRAW
Ethanoic acid CH3COOH DRAW
Propanoic acid CH3CH2COOH DRAW
91. Fats and oils
■ Ethanol ahs OH and ethanoic acid has OH with a double bond of O.
■ Fats:
– Esters
– Saturated
– Bromine water = stays orange
– Solid at room temperature
■ Oils:
– Esters
– Unsaturated
– Decolourises bromine water
– Liquid at room temperature
92. Method to make soap
■ Place 2g of solid fat or 2cm3 of oil into a beaker.
■ Add 10cm3 of concentrated sodium hydroxide solution.
■ Warm the beaker gently and stir with a glass rod until it boils.
■ Boil for 5mins and keep stirring.
■ Take off heat and add 10cm3 of distilled water and 5 spatulas of salt.
■ Boil for another 2-3mins.
■ Leave to cool then filter off the solid soap.
■ Wash product with a little distilled water and allow to dry.
■ Test the soap with a little water and shake. Did you get a good lather?
■ Also test with pH paper.
93. Soap – glycerol tristearate
■ Boil fats/oils with concentrated alkali.
■ Esters break down to form
– An alcohol called glycerol
– Sodium stearate (long chain carboxylic acid salts).
■ Sodium hydroxide + glycerol tristearate → sodium stearate + glycerol.
■ Concentrated alkali + oil/fat → soap + glycerol
94. How does soap work?
■ The active part of the soap is the anion (stearate group).
■ The head is hydrophilic (water loving) which dissolves in water.
■ The tail is hydrophobic (water hating) which dissolves in oily dirt/grease.
■ The hydrophobic tails dissolve in the grease and the hydrophilic head dissolves in the
water.
■ Some of the soap anions get beneath the grease and start to lift it off the fabric.
■ Grease leaves the fabric, surrounded by soap anions and mixes with the water.
95. Turning oil into fats
■ Hydrogenation of ethene:
■ Oils (unsaturated hydrocarbons) are reacted with hydrogen, in the presence of a catalyst.
■ This converts the C = C double bonds in the oils into into C – C single saturated bonds.
■ = catalytic hydrogenation.
C = C
H
C
HH
H
+ H2 → C - C
H
C
H
H
H
H
H