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Chemistry notes class 11 chapter 3 classification of elements and periodicity...AMARJEET KUMAR
This document provides an overview of the history of classifying elements and the development of the periodic table. It discusses early classification systems proposed by Prout, Dobereiner, Newlands and others. Meyer proposed classifying elements based on an atomic volume curve. Mendeleev created the first recognizable periodic table in 1869, which was improved upon over time. Key periodic properties like atomic radius, ionization energy, electronegativity and valency are explained in relation to an element's position on the periodic table. The modern periodic table is based on atomic number and has 18 groups and 7 periods.
The document discusses the history and development of the periodic table from Dobereiner's law of triads to Mendeleev's periodic table to the modern periodic table. It summarizes key features of the modern periodic table including its organization into periods and groups based on atomic number, trends in properties from period to period and group to group, and classification of elements into s, p, d and f blocks based on electron configuration.
Chapter - 5, Periodic Classification of Elements, Science, Class 10Shivam Parmar
I have expertise in making educational and other PPTs. Email me for more PPTs at a very reasonable price that perfectly fits in your budget.
Email: parmarshivam105@gmail.com
Chapter-5, Periodic Classification of Elements, Science Class10
CLASSIFICATION
DOBEREINER’S TRIAD
LIMITATIONS
NEWLAND’S LAW OF OCTAVES
CHARACTERISTICS OF LAW OF OCTAVES
LIMITATIONS OF NEWLANDS LAW OF OCTAVES
MENDELEEV’S PERIODIC TABLE
PROPERTIES OF GROUPS STUDIED BY MENDELEEV
LIMITATIONS OF MENDELEEV’S PERIODIC TABLE
MERITS OF MENDELEEV’S PERIODIC CLASSIFICATION
MODERN PERIODIC LAW
PROPERTIES OF MODERN PERIODIC TABLE
NOBLE GASES
POSITION OF ELEMENTS IN THE MODERN PERIODIC -TABLE
METALS
NON-METALS
METALLOIDS
TRENDS IN MODERN PERIODIC TABLE
Every topic of this chapter is well written concisely and visuals will help you in understanding and imagining the practicality of all the topics.
By Shivam Parmar (Entrepreneur & Teacher)
The document summarizes key aspects of the periodic table. It describes how the periodic table is organized into rows called periods and columns called families or groups. Elements in the same group have similar properties. Metals are on the left and center of the table, while non-metals are on the right. Metalloids separate metals and non-metals. Chemical families have elements with similar properties, such as alkali metals in Group 1 reacting easily with water and air. The number of valence electrons increases from left to right across a period and decreases down a group.
Carbon is a nonmetallic element that forms covalent bonds and exists in multiple allotropes depending on how its atoms are arranged. It can form linear, branched, or cyclic hydrocarbons ranging from methane with one carbon to complex molecules like cellulose. Key properties depend on factors like the number of carbon atoms, their arrangement into straight chains, branches, or rings, and whether bonds are single or double. Functional groups determine characteristic reactions by specific atoms within organic molecules.
The document summarizes key aspects of the periodic table, including its discovery by Dmitri Mendeleev who predicted undiscovered elements, and the periodic law stating elements' properties repeat periodically with their atomic number. It describes the main categories of elements as metals, nonmetals, and metalloids, and explains parts of the periodic table including periods and groups. It provides details on each group's properties including electron configuration, reactivity, and shared physical traits.
1.Periodic Properties & Variations of Properties Class 10 ,ICSE.pptxolgaYunas3
(i) Periodic properties and their variations in groups and periods.
(ii) Periodicity on the basis of atomic number for elements.
1.atomic size
2. ionisation POTENTIAL/
3,electron affinity
4. metals
non metals
5. density
Periodic Trends
Periods
groups
Mendeleev periodic table
Moseley periodic table
long form of periodic table
Atoms are the smallest particles that make up all matter. John Dalton's atomic theory states that all matter is made of tiny indivisible particles called atoms. Atoms of different elements have different masses and chemical properties. Two or more atoms can combine to form molecules, which are the smallest units that retain the properties of a substance. Molecules are formed when atoms bond together via chemical bonds and are the smallest particles that can exist independently. Common examples of molecules include water (H2O) and oxygen (O2).
Chemistry notes class 11 chapter 3 classification of elements and periodicity...AMARJEET KUMAR
This document provides an overview of the history of classifying elements and the development of the periodic table. It discusses early classification systems proposed by Prout, Dobereiner, Newlands and others. Meyer proposed classifying elements based on an atomic volume curve. Mendeleev created the first recognizable periodic table in 1869, which was improved upon over time. Key periodic properties like atomic radius, ionization energy, electronegativity and valency are explained in relation to an element's position on the periodic table. The modern periodic table is based on atomic number and has 18 groups and 7 periods.
The document discusses the history and development of the periodic table from Dobereiner's law of triads to Mendeleev's periodic table to the modern periodic table. It summarizes key features of the modern periodic table including its organization into periods and groups based on atomic number, trends in properties from period to period and group to group, and classification of elements into s, p, d and f blocks based on electron configuration.
Chapter - 5, Periodic Classification of Elements, Science, Class 10Shivam Parmar
I have expertise in making educational and other PPTs. Email me for more PPTs at a very reasonable price that perfectly fits in your budget.
Email: parmarshivam105@gmail.com
Chapter-5, Periodic Classification of Elements, Science Class10
CLASSIFICATION
DOBEREINER’S TRIAD
LIMITATIONS
NEWLAND’S LAW OF OCTAVES
CHARACTERISTICS OF LAW OF OCTAVES
LIMITATIONS OF NEWLANDS LAW OF OCTAVES
MENDELEEV’S PERIODIC TABLE
PROPERTIES OF GROUPS STUDIED BY MENDELEEV
LIMITATIONS OF MENDELEEV’S PERIODIC TABLE
MERITS OF MENDELEEV’S PERIODIC CLASSIFICATION
MODERN PERIODIC LAW
PROPERTIES OF MODERN PERIODIC TABLE
NOBLE GASES
POSITION OF ELEMENTS IN THE MODERN PERIODIC -TABLE
METALS
NON-METALS
METALLOIDS
TRENDS IN MODERN PERIODIC TABLE
Every topic of this chapter is well written concisely and visuals will help you in understanding and imagining the practicality of all the topics.
By Shivam Parmar (Entrepreneur & Teacher)
The document summarizes key aspects of the periodic table. It describes how the periodic table is organized into rows called periods and columns called families or groups. Elements in the same group have similar properties. Metals are on the left and center of the table, while non-metals are on the right. Metalloids separate metals and non-metals. Chemical families have elements with similar properties, such as alkali metals in Group 1 reacting easily with water and air. The number of valence electrons increases from left to right across a period and decreases down a group.
Carbon is a nonmetallic element that forms covalent bonds and exists in multiple allotropes depending on how its atoms are arranged. It can form linear, branched, or cyclic hydrocarbons ranging from methane with one carbon to complex molecules like cellulose. Key properties depend on factors like the number of carbon atoms, their arrangement into straight chains, branches, or rings, and whether bonds are single or double. Functional groups determine characteristic reactions by specific atoms within organic molecules.
The document summarizes key aspects of the periodic table, including its discovery by Dmitri Mendeleev who predicted undiscovered elements, and the periodic law stating elements' properties repeat periodically with their atomic number. It describes the main categories of elements as metals, nonmetals, and metalloids, and explains parts of the periodic table including periods and groups. It provides details on each group's properties including electron configuration, reactivity, and shared physical traits.
1.Periodic Properties & Variations of Properties Class 10 ,ICSE.pptxolgaYunas3
(i) Periodic properties and their variations in groups and periods.
(ii) Periodicity on the basis of atomic number for elements.
1.atomic size
2. ionisation POTENTIAL/
3,electron affinity
4. metals
non metals
5. density
Periodic Trends
Periods
groups
Mendeleev periodic table
Moseley periodic table
long form of periodic table
Atoms are the smallest particles that make up all matter. John Dalton's atomic theory states that all matter is made of tiny indivisible particles called atoms. Atoms of different elements have different masses and chemical properties. Two or more atoms can combine to form molecules, which are the smallest units that retain the properties of a substance. Molecules are formed when atoms bond together via chemical bonds and are the smallest particles that can exist independently. Common examples of molecules include water (H2O) and oxygen (O2).
Topics Included
• Introduction
• Metals
→ Physical properties of metals
→ Chemical Properties of metals
• Non-metals
→ Physical properties of non-metals
→ Chemical Properties of metals
• Difference between metals and non-metals
• Reaction with Acids
• Reaction with Bases
The periodic table arranges the elements based on atomic number and chemical properties. It is divided into metals, nonmetals, and metalloids. The periodic table predicts chemical behavior, trends, and element properties. It organizes elements by atomic structure, number, and physical/chemical traits.
Periodic Properties of Elements (Class X CBSE & ICSE)KeyurMaradiya
The document discusses the history and development of the periodic table. It explains that early scientists like Dobereiner and Newlands attempted to classify elements but their systems had limitations. Mendeleev created the first successful periodic table in 1869 by arranging elements by atomic mass and leaving gaps for undiscovered elements. The modern periodic table is arranged by atomic number based on the repeating properties of elements, and classifies elements into blocks and groups with similar properties. The periodic table provides an organized framework for studying and predicting the properties of all known elements.
The document discusses the structure and organization of the modern periodic table. Elements are arranged horizontally in order of increasing atomic number and grouped vertically into columns based on their electron configurations. The periodic table is divided into blocks including s-, p-, d- and f-blocks. An element's position in the table is determined by its atomic number and electron configuration, especially the outermost electrons.
Atomic radii decrease across a period as nuclear charge increases. Cations are smaller than their parent atoms. Among isoelectronic species, the one with the larger positive nuclear charge will have the smallest radius. Ionization energy generally increases across a period as it is more difficult to remove electrons, and decreases down a group as shielding increases. Electronegativity follows similar trends as ionization energy.
The document discusses the organization and classification of elements in the periodic table. It describes how Mendeleev organized the elements based on increasing atomic mass and similar properties. The modern periodic table is organized by increasing atomic number. Elements are classified into metals, nonmetals, and metalloids, which are grouped based on their location on the periodic table. Each group of elements has a characteristic number of valence electrons that determine their chemical properties.
Periodic classification of elements Grade-11Paneru DP
The document discusses the periodic classification of elements. It provides the atomic numbers, symbols, and atomic masses of the first 30 elements in the periodic table. It then discusses the key features and components of modern periodic tables, including that elements are arranged by atomic number rather than atomic mass. The modern periodic table contains 7 periods and 18 groups, with elements in the same group having the same number of electrons in their outer shell. It also notes the advantages of the modern periodic table over previous classifications.
An atom is the smallest particle of an element that contains protons, neutrons, and electrons. Elements are substances made of a single type of atom that combine to form molecules, which are made of two or more atoms joined together. Molecules such as water, written as H2O with two hydrogen atoms and one oxygen atom, are the smallest particles that combine without chemical change to form all matter in the world.
Atoms, elements, compounds and mixtures.pptxSoniaTaneja15
1) The document discusses atoms, elements, compounds, and mixtures. It aims to explain what an atom is, differentiate between elements, compounds and mixtures, and give examples of each.
2) Atoms are the basic building blocks of all matter and are very small. Elements are substances made of only one type of atom that cannot be broken down further.
3) Compounds are formed when two or more elements are chemically bonded together and have different properties than the original elements. Mixtures contain two or more substances that are not chemically bonded and can be separated.
Meristematic tissue is a plant tissue that is undifferentiated and can divide to form other tissues. It is found in three main regions: the apical meristem at the tips of stems and roots, the intercalary meristem at the bases of leaves and stems, and the lateral meristem or cambium responsible for increasing the girth of stems and roots. Permanent tissues are differentiated tissues that do not divide, such as parenchyma, collenchyma and sclerenchyma. Epithelial tissue forms protective layers in animals, such as the skin and lining of organs, while connective tissue binds and supports other tissues.
Elements are pure substances that cannot be broken down further through chemical or physical means. There are currently 118 known elements, with new ones occasionally being discovered through artificial nuclear reactions. Elements are identified by their atomic number, which represents the number of protons in the nucleus. Elements are the basic building blocks of all matter and are used to create thousands of materials, though some like plutonium are also used in nuclear weapons due to their radioactive properties.
This document is a PowerPoint presentation on carbon and its compounds submitted by a student group. It provides information on carbon including that it is a nonmetallic element with an atomic number of 6 that forms covalent bonds. It discusses the origin of carbon in nature, the reasons for its versatility including catenation and tetracovalency. The presentation also covers different forms of carbon including graphite, diamond and fullerenes as well as saturated and unsaturated compounds. It provides examples of functional groups and homologous series and discusses chemical properties and uses of carbon compounds.
The document discusses the development of the periodic table. It describes early classification systems by Dobereiner and Newlands that grouped elements based on properties but had limitations as new elements were discovered. Mendeleev organized the elements into the first recognizable periodic table based on atomic mass and predicted properties of undiscovered elements. Moseley later modified this to be based on atomic number. The modern periodic table is arranged into periods and groups with trends in properties like atomic radius, ionization potential, and electronegativity explained by variation in nuclear charge and number of electron shells across and down the table.
The periodic table organizes 118 known elements and displays their symbols and names. It arranges elements in rows called periods and columns called groups based on their atomic structure and properties. Elements in the same group have the same number of outer electrons and similar chemical properties, while properties vary greatly across each period from very reactive solids to inactive gases. The periodic table provides a way to classify and compare elements according to their atomic number and mass.
The document summarizes the history and development of the periodic table. It describes how early chemists like Cannizzaro, Mendeleev, and Moseley contributed to organizing the elements based on their atomic masses and properties. The modern periodic table is arranged by increasing atomic number and groups elements with similar properties together in periods and families. Key periodic properties like atomic radius, ionization energy, and electronegativity are influenced by an element's position on the table.
Chemistry(class11)-CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIESPawan Kumar
The document discusses the history and development of the periodic table. It explains that:
1) Elements have been organized into the periodic table based on their atomic weights and properties in order to systematically study and predict chemical behavior.
2) Early periodic tables were proposed by scientists like Dobereiner, Newlands, and Mendeleev based on trends in atomic weights, though Mendeleev's 1869 table was the most successful in predicting new elements.
3) Modern periodic tables are arranged by atomic number according to the periodic law proposed by Moseley, with elements grouped into blocks based on their electron configurations. The table better explains trends in physical and chemical properties.
The document discusses the structure of atoms and their composition. It explains that atoms are composed of a tiny, dense nucleus containing protons and neutrons, surrounded by electrons in defined orbits. Niels Bohr revised earlier atomic models by suggesting that electrons occupy specific orbits and can jump between these orbits by absorbing or emitting energy. The arrangement of electrons in an atom is called its electronic configuration. Atoms of the same element can have different numbers of neutrons, forming isotopes with the same chemical properties but different physical properties. Isotopes have applications including use in nuclear power and medical treatments.
Periodic Classification of Elements and PeriodicityNEHANEHA67
The document discusses the history and development of the periodic table. It explains that early scientists like Dobereiner and Newlands began classifying elements based on their properties, but that Dmitri Mendeleev created the first recognizable periodic table in 1871. His table arranged elements in order of atomic mass and predicted properties of undiscovered elements. Later, Moseley's discovery of atomic number allowed the modern periodic table to arrange elements by atomic number instead of mass. The document also discusses trends in properties within the periodic table.
This document summarizes key concepts from Chapter 5 on the periodic classification of elements:
1. Early scientists like Dobereiner and Newlands attempted to classify elements based on their properties but their systems did not comprehensively explain the trends.
2. Mendeleev organized the known elements into the first periodic table based on their atomic masses and properties, noting periodic trends. This helped predict new elements.
3. Modern periodic tables are organized by atomic number not mass, reflecting Moseley's discovery of each element's unique atomic number. Periodic trends exist in properties like size, valence, and metallicity across periods and groups.
This document discusses chemical bonding and macromolecular structures. It begins by explaining the different types of bonds - ionic bonds formed between metals and non-metals by electron transfer, and covalent bonds formed between non-metals by electron sharing. It describes the properties of ionic and covalent compounds. It then discusses macromolecular structures found in substances like diamond, graphite and metals. It explains metallic bonding and compares the structures and properties of diamond and graphite. In the end, it discusses the different uses of diamond and graphite based on their properties.
Periodic calssification of elements ncert shashikumar b sghsykhalli
The document provides an overview of the periodic classification of elements. It discusses early attempts at classification including Dobereiner's triads and Newlands' law of octaves. It then covers Mendeleev's periodic table, including its merits and defects. Finally, it describes the modern periodic table based on atomic number, including periodic trends in properties like atomic size and electronegativity across periods and down groups. Key topics covered include the groups and periods in the modern table, how to read and understand its layout, and common questions about periodic trends and properties.
The history of the periodic table's development, the arrangement of the elements, and the reactivity of each group of elements will all be covered in this lecture.
Topics Included
• Introduction
• Metals
→ Physical properties of metals
→ Chemical Properties of metals
• Non-metals
→ Physical properties of non-metals
→ Chemical Properties of metals
• Difference between metals and non-metals
• Reaction with Acids
• Reaction with Bases
The periodic table arranges the elements based on atomic number and chemical properties. It is divided into metals, nonmetals, and metalloids. The periodic table predicts chemical behavior, trends, and element properties. It organizes elements by atomic structure, number, and physical/chemical traits.
Periodic Properties of Elements (Class X CBSE & ICSE)KeyurMaradiya
The document discusses the history and development of the periodic table. It explains that early scientists like Dobereiner and Newlands attempted to classify elements but their systems had limitations. Mendeleev created the first successful periodic table in 1869 by arranging elements by atomic mass and leaving gaps for undiscovered elements. The modern periodic table is arranged by atomic number based on the repeating properties of elements, and classifies elements into blocks and groups with similar properties. The periodic table provides an organized framework for studying and predicting the properties of all known elements.
The document discusses the structure and organization of the modern periodic table. Elements are arranged horizontally in order of increasing atomic number and grouped vertically into columns based on their electron configurations. The periodic table is divided into blocks including s-, p-, d- and f-blocks. An element's position in the table is determined by its atomic number and electron configuration, especially the outermost electrons.
Atomic radii decrease across a period as nuclear charge increases. Cations are smaller than their parent atoms. Among isoelectronic species, the one with the larger positive nuclear charge will have the smallest radius. Ionization energy generally increases across a period as it is more difficult to remove electrons, and decreases down a group as shielding increases. Electronegativity follows similar trends as ionization energy.
The document discusses the organization and classification of elements in the periodic table. It describes how Mendeleev organized the elements based on increasing atomic mass and similar properties. The modern periodic table is organized by increasing atomic number. Elements are classified into metals, nonmetals, and metalloids, which are grouped based on their location on the periodic table. Each group of elements has a characteristic number of valence electrons that determine their chemical properties.
Periodic classification of elements Grade-11Paneru DP
The document discusses the periodic classification of elements. It provides the atomic numbers, symbols, and atomic masses of the first 30 elements in the periodic table. It then discusses the key features and components of modern periodic tables, including that elements are arranged by atomic number rather than atomic mass. The modern periodic table contains 7 periods and 18 groups, with elements in the same group having the same number of electrons in their outer shell. It also notes the advantages of the modern periodic table over previous classifications.
An atom is the smallest particle of an element that contains protons, neutrons, and electrons. Elements are substances made of a single type of atom that combine to form molecules, which are made of two or more atoms joined together. Molecules such as water, written as H2O with two hydrogen atoms and one oxygen atom, are the smallest particles that combine without chemical change to form all matter in the world.
Atoms, elements, compounds and mixtures.pptxSoniaTaneja15
1) The document discusses atoms, elements, compounds, and mixtures. It aims to explain what an atom is, differentiate between elements, compounds and mixtures, and give examples of each.
2) Atoms are the basic building blocks of all matter and are very small. Elements are substances made of only one type of atom that cannot be broken down further.
3) Compounds are formed when two or more elements are chemically bonded together and have different properties than the original elements. Mixtures contain two or more substances that are not chemically bonded and can be separated.
Meristematic tissue is a plant tissue that is undifferentiated and can divide to form other tissues. It is found in three main regions: the apical meristem at the tips of stems and roots, the intercalary meristem at the bases of leaves and stems, and the lateral meristem or cambium responsible for increasing the girth of stems and roots. Permanent tissues are differentiated tissues that do not divide, such as parenchyma, collenchyma and sclerenchyma. Epithelial tissue forms protective layers in animals, such as the skin and lining of organs, while connective tissue binds and supports other tissues.
Elements are pure substances that cannot be broken down further through chemical or physical means. There are currently 118 known elements, with new ones occasionally being discovered through artificial nuclear reactions. Elements are identified by their atomic number, which represents the number of protons in the nucleus. Elements are the basic building blocks of all matter and are used to create thousands of materials, though some like plutonium are also used in nuclear weapons due to their radioactive properties.
This document is a PowerPoint presentation on carbon and its compounds submitted by a student group. It provides information on carbon including that it is a nonmetallic element with an atomic number of 6 that forms covalent bonds. It discusses the origin of carbon in nature, the reasons for its versatility including catenation and tetracovalency. The presentation also covers different forms of carbon including graphite, diamond and fullerenes as well as saturated and unsaturated compounds. It provides examples of functional groups and homologous series and discusses chemical properties and uses of carbon compounds.
The document discusses the development of the periodic table. It describes early classification systems by Dobereiner and Newlands that grouped elements based on properties but had limitations as new elements were discovered. Mendeleev organized the elements into the first recognizable periodic table based on atomic mass and predicted properties of undiscovered elements. Moseley later modified this to be based on atomic number. The modern periodic table is arranged into periods and groups with trends in properties like atomic radius, ionization potential, and electronegativity explained by variation in nuclear charge and number of electron shells across and down the table.
The periodic table organizes 118 known elements and displays their symbols and names. It arranges elements in rows called periods and columns called groups based on their atomic structure and properties. Elements in the same group have the same number of outer electrons and similar chemical properties, while properties vary greatly across each period from very reactive solids to inactive gases. The periodic table provides a way to classify and compare elements according to their atomic number and mass.
The document summarizes the history and development of the periodic table. It describes how early chemists like Cannizzaro, Mendeleev, and Moseley contributed to organizing the elements based on their atomic masses and properties. The modern periodic table is arranged by increasing atomic number and groups elements with similar properties together in periods and families. Key periodic properties like atomic radius, ionization energy, and electronegativity are influenced by an element's position on the table.
Chemistry(class11)-CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIESPawan Kumar
The document discusses the history and development of the periodic table. It explains that:
1) Elements have been organized into the periodic table based on their atomic weights and properties in order to systematically study and predict chemical behavior.
2) Early periodic tables were proposed by scientists like Dobereiner, Newlands, and Mendeleev based on trends in atomic weights, though Mendeleev's 1869 table was the most successful in predicting new elements.
3) Modern periodic tables are arranged by atomic number according to the periodic law proposed by Moseley, with elements grouped into blocks based on their electron configurations. The table better explains trends in physical and chemical properties.
The document discusses the structure of atoms and their composition. It explains that atoms are composed of a tiny, dense nucleus containing protons and neutrons, surrounded by electrons in defined orbits. Niels Bohr revised earlier atomic models by suggesting that electrons occupy specific orbits and can jump between these orbits by absorbing or emitting energy. The arrangement of electrons in an atom is called its electronic configuration. Atoms of the same element can have different numbers of neutrons, forming isotopes with the same chemical properties but different physical properties. Isotopes have applications including use in nuclear power and medical treatments.
Periodic Classification of Elements and PeriodicityNEHANEHA67
The document discusses the history and development of the periodic table. It explains that early scientists like Dobereiner and Newlands began classifying elements based on their properties, but that Dmitri Mendeleev created the first recognizable periodic table in 1871. His table arranged elements in order of atomic mass and predicted properties of undiscovered elements. Later, Moseley's discovery of atomic number allowed the modern periodic table to arrange elements by atomic number instead of mass. The document also discusses trends in properties within the periodic table.
This document summarizes key concepts from Chapter 5 on the periodic classification of elements:
1. Early scientists like Dobereiner and Newlands attempted to classify elements based on their properties but their systems did not comprehensively explain the trends.
2. Mendeleev organized the known elements into the first periodic table based on their atomic masses and properties, noting periodic trends. This helped predict new elements.
3. Modern periodic tables are organized by atomic number not mass, reflecting Moseley's discovery of each element's unique atomic number. Periodic trends exist in properties like size, valence, and metallicity across periods and groups.
This document discusses chemical bonding and macromolecular structures. It begins by explaining the different types of bonds - ionic bonds formed between metals and non-metals by electron transfer, and covalent bonds formed between non-metals by electron sharing. It describes the properties of ionic and covalent compounds. It then discusses macromolecular structures found in substances like diamond, graphite and metals. It explains metallic bonding and compares the structures and properties of diamond and graphite. In the end, it discusses the different uses of diamond and graphite based on their properties.
Periodic calssification of elements ncert shashikumar b sghsykhalli
The document provides an overview of the periodic classification of elements. It discusses early attempts at classification including Dobereiner's triads and Newlands' law of octaves. It then covers Mendeleev's periodic table, including its merits and defects. Finally, it describes the modern periodic table based on atomic number, including periodic trends in properties like atomic size and electronegativity across periods and down groups. Key topics covered include the groups and periods in the modern table, how to read and understand its layout, and common questions about periodic trends and properties.
The history of the periodic table's development, the arrangement of the elements, and the reactivity of each group of elements will all be covered in this lecture.
1. The document discusses the historical development of the periodic table from Dobereiner's classification of elements into triads to Moseley's ordering of all elements by their atomic number.
2. Mendeleev's periodic table was a significant improvement as it predicted future elements and organized elements into periods and groups according to chemical properties.
3. The modern periodic table is based on Moseley's work classifying elements by atomic number, with elements in the same group having the same number of valence electrons and similar chemical properties.
This document discusses the periodic table and classification of elements. It explains that elements are arranged in the periodic table in order of increasing atomic number. The table is divided into blocks based on the subshell where electrons are located (s, p, d, f blocks). Elements are also classified into groups based on their physical and chemical properties. The modern periodic table improved upon earlier versions by being based on the fundamental property of atomic number, better correlating an element's position with its electronic configuration.
Mendeleev arranged elements in increasing order of atomic mass and placed those with similar properties in the same group, forming the first periodic table. This allowed for accurate prediction of undiscovered elements and correction of atomic masses. The modern periodic table is arranged by atomic number, with elements in periods by electron shell and groups by valence electrons. Trends across periods include decreasing atomic size and metallic character from left to right as nuclear charge increases, while trends down groups include increasing size and metallic character as shells are added.
This document discusses the development of the periodic table from early classification attempts to the modern periodic table. It describes Dobereiner's discovery of triads of elements with similar properties in the 1810s. It then discusses Newlands' law of octaves from the 1860s which noted patterns every eighth element. Mendeleev developed the first periodic table in 1869, arranging elements by atomic mass and leaving gaps for undiscovered elements. The modern periodic table is arranged by atomic number instead of mass and helped resolve limitations of earlier classifications. It describes trends in properties like valency and size across periods and groups in the modern periodic table.
Chapter 9 periodic classification of elementsAbdulWaseem33
This document provides information about the periodic classification of elements. It discusses early classification schemes proposed by Dobereiner and Newlands, and their limitations. It then describes Mendeleev's periodic table from 1869, which arranged elements in order of increasing atomic mass and predicted new elements. The document outlines properties of groups studied by Mendeleev and limitations of his table. Finally, it discusses the modern periodic law and properties of the modern periodic table, including trends in atomic size, ionization energy, and metallic character across periods and down groups.
CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIESniralipatil
The document discusses the classification of elements and the development of the periodic table over time. It describes early attempts at classification by Dobereiner, Newlands, and Mendeleev. Mendeleev organized the elements into the first periodic table based on increasing atomic mass. Later, Moseley established the modern periodic table based on increasing atomic number. The document outlines the structural features and characteristics of the main blocks (s, p, d, f) of the periodic table. It also defines atomic properties like atomic radius, covalent radius, and metallic radius, and how they vary within the periodic table.
The periodic table organizes the elements according to increasing atomic number. Early scientists like Dobereiner, Newlands, and Mendeleev made attempts to classify elements, with Mendeleev devising the first successful periodic table. Mendeleev arranged elements with similar properties into columns and left gaps for elements not yet discovered. The periodic table provides information on elemental properties like valency, atomic size, metallic character, and electronegativity based on an element's position.
Periodic Classification Of Elements Class 10thNehaRohtagi1
Johann Wolfgang Döbereiner studied chemistry and became a professor of chemistry and pharmacy. He discovered similar triads of elements with increasing atomic masses, which led to the development of the periodic table. John Newlands arranged elements in order of increasing atomic mass and found they repeated properties every eighth element, calling this the Law of Octaves. However, this law did not apply to all elements as more were discovered. Dmitri Mendeleev arranged elements based on atomic mass and chemical properties, leaving gaps for undiscovered elements, which contributed greatly to the early periodic table. The modern periodic table is based on atomic number according to Henry Moseley's discovery that it is a more fundamental property than atomic mass.
This document discusses the classification and periodic trends of chemical elements. It begins by outlining early classification systems developed by Dobereiner, Newlands, Meyer and Mendeleev that organized elements by their increasing atomic masses and recognized periodic trends in their properties. Mendeleev organized the elements into the first periodic table. Later, Moseley determined that atomic number, not atomic mass, was fundamental in organizing elements. This led to the modern periodic table arranged by increasing atomic number. The document then discusses the organization and features of the long form periodic table, including grouping elements by their electronic configurations and periodic trends in physical and chemical properties.
The document discusses the organization and structure of the periodic table. It describes how elements are arranged based on their atomic structure and properties. Elements are organized by increasing atomic number and grouped according to similar characteristics. The periodic table displays the symbols, names, atomic numbers and masses of each element.
The document discusses the organization and structure of the periodic table. It describes how elements are arranged based on their atomic structure and properties. Elements are organized by increasing atomic number and grouped according to similar characteristics. The periodic table displays the symbols, names, atomic numbers and masses of each element.
The document discusses the history of the periodic classification of elements from early systems proposed by Lavoisier, Dalton, Dobereiner, and Newlands to Mendeleev's periodic table. It outlines some of the key developments and properties used in their classification schemes, including atomic weight and electronic configuration. The modern periodic table is based on atomic number according to Moseley's discovery that properties are periodic functions of atomic number rather than atomic weight. The document also discusses periodic trends in properties like atomic radius, metallic character, electronegativity, and their relationship to position in the periodic table.
For educational purposes only. No copyright intended to use the material. Credited the owner of the ppt. This is only for reference for the topic of Grade 8 Science in TNHS 2023-2024
The document summarizes key aspects of the periodic table, including its structure, historical development, and trends in elemental properties. It explains that the periodic table arranges elements in rows and columns based on atomic number and properties. Mendeleev and Moseley helped develop the modern periodic table by arranging elements based on atomic mass and charge. Elements are classified as metals, nonmetals, and metalloids based on their physical and chemical properties, which vary predictably within and between groups and periods.
Classification of elements periodicity properties IUPAC names 100 to 118SURI BABU JOGA
This document discusses the classification of elements and periodic trends in their physical and chemical properties. It begins with an overview of how elements have historically been classified from Dobereiner's triads to Mendeleev's periodic table. Key periodic properties discussed include atomic radius, ionization energy, and electronegativity. Periodic trends in these properties are explained in terms of the periodic variation in the effective nuclear charge experienced by outer shell electrons due to shielding effects. Chemical properties also vary periodically, including oxidation states and reactivity. The document aims to explain these periodic trends using concepts of electronic configuration.
The document provides information about the periodic table of elements and related concepts:
1) The periodic table arranges the chemical elements by atomic number and electron configuration, showing periodic trends in properties. Elements are grouped into blocks by their electron configurations and periods by the filling of electron shells.
2) Key concepts discussed include atomic number, electron configuration, chemical properties, periodic trends, metals, nonmetals, groups such as halogens and noble gases, periods, and shells and subshells.
3) Dmitri Mendeleev is credited with publishing the first recognizable periodic table in 1869, organizing known elements and predicting properties of undiscovered elements. His work established the basis for the modern periodic table
Welcome to the project dedicated to the remarkable Periodic Table of Elements! Prepare to embark on an exciting exploration of the building blocks of our universe through our comprehensive presentation.
Our presentation offers a captivating visual representation of the Periodic Table, showcasing the elements and their essential properties. Each element is presented with its atomic number, symbol, and atomic mass, providing a clear overview of the entire table.
Delve deeper into the presentation and unlock a wealth of knowledge about each element. Discover their unique characteristics, such as their physical and chemical properties, common uses, and even their historical significance. Engaging narratives and captivating illustrations bring the elements to life, making the learning experience both enjoyable and informative.
Whether you're a student, a science enthusiast, or simply curious about the elements that shape our world, our presentation on the Periodic Table will enlighten and inspire. Join us on this educational journey as we unravel the mysteries and marvels of the elements that surround us.
Periodic Table (Classification of elements) MANIKImran Nur Manik
Electronic structure of atoms, modern periodic table and periodic law, variation of periodic properties within periods and groups, ionization potential, electron affinity, electronegativity, usefulness and limitation of periodic table.
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Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
2. Classification of elements
● The earlier attempt to classify elements involve dividing them into metals and
nonmetals.
● The classification was done by Antoine Laurent Lavoisier (Father of
chemistry).
● This method failed because most of the elements were metals and a very few
were non metals.
● Some elements resembled metals and nonmetals and hence they could not
be classified.
3. Dobereiner's triads
● In the year 1817, Johann Wolfgang Dobereiner,
a German chemist classified elements having
similar properties into groups called triads.
● When the elements were arranged in groups of 3, in the
increasing order of atomic masses, the middle element
has the atomic mass and properties roughly the average
of the other two elements.
4. Alkali metal group Alkaline earth metal group
Element At: mass Element At: mass
Li 7 Ca 40
Na 23 Sr 88
K 39 Ba 137
Halogen group
Element At: mass
Cl 35.5
Br 80
I 127
5. Newlands law of Octaves - John Newland
When elements are arranged in the increasing order of their atomic masses (from
H to Th), the properties of the 8th element resembled with the properties of the
first element. This was compared to the octaves found in music. Hence called
Newlands law of octaves.
6. Demerits of Newland’s Law of Octaves
● It was found that the Law of Octaves was applicable only upto calcium, as after
calcium every eighth element did not possess properties similar to that of the
first.
● It was assumed by Newlands that only 56 elements existed in nature and no
more elements would be discovered in the future. But, later on, several new
elements were discovered, whose properties did not fit into the Law of Octaves.
● In order to fit elements into his Table, Newlands adjusted two elements in the
same slot, but also put some unlike elements under the same note. Cobalt and
nickel are in the same slot and these are placed in the same column as fluorine,
chlorine and bromine which have very different properties than these elements.
Iron, which resembles cobalt and nickel in properties, has been placed far away
from these elements. Thus, Newlands’ Law of Octaves worked well with lighter
elements only.
7. Mendeleev’s Periodic Law - Dmitri Ivanovich
Mendeleev
When Mendeleev started his work , 63 elements were known.
He examined the relationship between the atomic masses of
the elements and their physical and chemical properties.
“ The properties of elements are a periodic function of their
atomic masses”
8.
9. Features of Mendeleev’s Periodic table.
● The vertical columns were called groups and horizontal
rows were called periods. There were 6 periods and 8
groups in the table.
● The elements in each group resembles with each other in
many properties.
● All the elements in the group show the same valency.
● The properties like atomic size, MP and BP changed
gradually in any period while going from left to right.
10. Advantages of Mendeleev’s Periodic table.
● Mendeleev could classify all the 63 elements discovered at that time
on the basis of similarity in properties.
● He left gaps for elements yet to be discovered. He named them by
prefixing the sanskrit numeral, Eka (One) to the name of the
preceding element in the same group. Eg: Scandium, gallium and
germanium have properties similar to Eka-Boron, Eka-Aluminium and
Eka-Silicon respectively.
● He predicted the properties of the undiscovered elements and helped
in the discovery of these elements.
● His periodic table could accommodate noble gases when they were
discovered.
● He could correct the masses of certain elements with respect to their
position in the table.
11. Limitations of Mendeleev’s Periodic table
● A correct position for hydrogen could not be given in the
periodic table. Hydrogen resembles alkali metals and halogens.
● The position of isotopes could not be explained.
● Wrong order of atomic mass of some elements could not be
explained. Eg: Cobalt (Atomic mass 58.9) appeared before
nickel (Atomic mass 58.7).
● Atomic mass do not increase in a regular manner. So it was not
possible to predict how many elements could be discovered
between two elements.
● He does not make any attempt to separate metals from
nonmetals.
12. Position of Hydrogen
● Hydrogen resembles alkali metals -
They combine with halogens, oxygen
and sulphur to form compounds
having similar formula.
● Like halogens, hydrogen is diatomic and it combines with
metals and nonmetals to form covalent compounds.
13. Modern Periodic Law
Henry Moseley showed that atomic number is a more
fundamental property than atomic mass.
“ Properties of elements are periodic function
of their atomic number”
14. ● Atomic number (Z) is the number of protons present in an
atom.
● Z increases by one in going from one element to the next.
● Prediction of properties of elements was more precise
with the arrangement of elements in the increasing order
of atomic number.
15.
16.
17.
18.
19.
20. New names added to the periodic table.
● 113 - Nh -Nihonium - Japan
● 115 - Mc - Moscovium - Moscow region
● 117 - Ts - Tennessine - Tennessee
● 118 - Og - Oganesson - Yuri Oganessian
21.
22. General features of long form periodic table
● The elements are arranged in the increasing order of
atomic number.
● There are 7 horizontal rows called periods.
● There are 18 vertical columns called groups.
● Elements having similar valence electrons are placed in
the same group.
● Each period starts with the filling of a new shell.
23. ● The 14 elements after Lanthanum are called lanthanoids.
● The 14 elements after Actinium are called actinoids
● To limit the size of the periodic table and to keep the
elements with similar properties together, Lanthanoids
and Actinoids are placed at the bottom of the periodic
table.
● The elements of group1, 2 and 13-17 (s-block and p-
block) are called representative elements or main group
elements. They have completely filled inner shells but
incomplete valence shell.
● The elements of group 3-12(d-block) are called
transition elements. They have incomplete outer shells
24. ● The elements placed at the bottom of the periodic table (f-
block) are called inner transition elements. They are also
called rare earth metals because they occur rarely in the
earth's crust.
● Group 18 elements are called noble gases or inert
gases. Their outer orbits are completely filled and are
unreactive.
● A zig-zag line separates metals from nonmetals by some
elements called metalloids or semimetals (B, Si, Ge, As,
Sb, Te and Po)
● Metals are found on the left side of the periodic table and
nonmetals on the right side.
25. Important points to note
● Elements in any group have same number of valence
electrons.
● Size of the atom decreases across a period and increases
down a group.
● Each period starts with a new shell.
● Maximum number of electrons in each shell is given by
the formula 2n2, where n is the number of the given shell.
(K=1, L=2, M=3, ….)
26.
27. Characteristics / trends of Modern periodic table
1. Valency - It is the combining capacity of an element. It
denotes the number of electrons lost or gained during a
chemical reaction.
● On moving from left to right in a period, valency of the
elements first increases from 1 to 4 and then decreases to
zero.
● All the elements in a group has same valency, as they
have same number of valence shell electrons.
28. 2. Atomic size:
● On moving from left to right in a period, the atomic size
(atomic radius) of the atom decreases.
● As we move from left to right in a period, the atomic
number increases, which means the number of protons
also increases. Due to the large positive charge on the
nucleus, the electrons are pulled in more closer to the
nucleus and size of the atom decreases.
● Down a group size of atom increases, as new shells are
added up.
29. 3. Metallic character:
● Metals are found on the left hand side of the table and
nonmetals on the right hand side.
● Metals has a tendency to lose electrons - electropositive.
● Nonmetals has a tendency to gain electrons -
electronegative.
● On moving from left to right in a period, the electropositive
character decreases and electro negative character
increases.
● On moving from left to right in a period, the tendency of
atoms to lose electrons decreases and tendency of atoms to
gain electron increases.
30. ● On moving down a group the metallic character of the
elements increases or the electropositive character of the
element increases.
● As we go down in group 17, the electronegative character
(nonmetallic character) of elements decreases.
● Fluorine is the most electronegative element.
31. 4. Chemical reactivity.
● Chemical reactivity of metals increases on going down a
group.
● Chemical reactivity of nonmetals decreases on going
down a group
● On moving from left to right in a period, the chemical
reactivity of elements first decreases and then increases.
32. 5. Nature of oxides.
● On moving from left to right in a period the basic nature of
oxides decreases and the acidic nature of oxides
increases.
● On moving down a group there is no change in the nature
of oxides of elements
● All elements of group 1 form basic oxides
● All the elements of group 17 form acidic oxides
33. 6. Ionisation Energy
● The energy required to remove the most loosely bound
electron from a gaseous neutral atom in the ground state
is known as Ionisation energy.
● It is expressed in Kj/mol.
● Ionisation energy increases with the increase in atomic
number across a period, due to the increase in nuclear
charge and decrease in atomic size.
● Ionisation energy decreases down a group due to the
increase in atomic size and increase in the shielding
effect.