types of reactions

1. 10.2 Classifying Chemical
Reactions
•Synthesis
•Combustion
•Decomposition
•Single Replacement
•Double Replacement

2. Synthesis Reactions
“The Dating Game”
• Two or more substances react to form
one product
– A + B  AB Word Equation:
Lithium metal and chlorine gas react to form
solid lithium chloride
Skeleton Equation:
Li(s) + Cl2(g) → LiCl(s)
Balanced Equation
2Li(s) + Cl2(g) → 2LiCl(s)

3. Synthesis Demo!!!
• Magnesium metal reacts with oxygen
gas and when heated produces solid
magnesium oxide.
• Equation:

4. Combustion Reactions
“where there’s smoke there’s
fire”
• An element or a compound reacts with
oxygen, producing energy in the form of
heat and light.
– i.e. H2(g) + O2(g)  H2O(g)
– This looks like a synthesis reaction!
• When the reactant is a hydrocarbon
(contains H and C), the product will be
carbon dioxide gas, water vapor, and
energy

5. Word Equation:
Propane gas (C3H8) in a grill reacts with oxygen gas
to yield carbon dioxide gas, water vapor and heat energ
Skeleton Equation:
C3H8(g) + O2(g) → CO2(g) + H2O(g) + energy
Balanced Equation:
C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) + energy

6. Combustion Demo!!!
• Methane gas (CH4) burns in a bunsen
burner.
• Equation:

7. Decomposition Reactions
“The Big Break-up”
• One substance decomposes to form two or
more products
– AB  A + B Word Equation:
Solid copper(I) carbonate when heated forms
solid
copper(I) oxide and carbon dioxide gas
Skeleton Equation:
Cu2CO3(s) → Cu2O(s) + CO2(g)
Balanced Equation:
Cu2CO3(s) → Cu2O(s) + CO2(g)

8. Decomposition Demo!!!
• Baking soda (sodium bicarbonate)
decomposes upon heating in to solid
sodium carbonate, carbon dioxide gas
and water vapor.
• Equation:

9. Single Replacement
Reactions
“The Bully Reaction”
• Atoms of one element replace the atoms
of a second element in a compound (A + BC
 BA or AC).
• For example, a metal replaces a metal
and a nonmetal replaces a
nonmetal…like replaces like!

10. Skeleton Equation:
Cu2SO4(aq) + Fe(s) → Cu(s) + FeSO4(aq)
Word Equation:
Aqueous copper(I) sulfate reacts with iron
metal to form copper metal and aqueous iron(II)
sulfate
Balanced Equation
Cu2SO4(aq) + Fe(s) → 2Cu(s) + FeSO4(aq)

11. Predicting Products
• When given 2 reactants, you should be
able to predict the products.
– Determine if the lone element is a metal
or a nonmetal.
– Determine the metal or nonmetal it will
replace in the compound.
– Check your activity series.
– Replace the metal/nonmetal in the
compound with the lone metal/nonmetal.
• Make sure to criss cross for the new
compound

12. Activity Series
• An activity series helps you to decide
if a single replacement reaction will
occur
• When looking at the activity series,
the elements that are listed first can
replace the elements listed after
them
• So, a reaction will happen if the
element to be replaced is lower than
the element doing the replacing!

13. Activity Series of Metals
Name
Lithium
Potassium
Calcium
Sodium
Magnesium
Aluminum
Zinc
Iron
Lead
Hydrogen
Copper
Mercury
Silver
Symbol
Li
K
Ca
Na
Mg
Al
Zn
Fe
Pb
H
Cu
Hg
Ag
DecreasingActivity

14. Activity of the halogens
Name
Fluorine
Chlorine
Bromine
Iodine
Symbol
F2
Cl2
Br2
I2
Decreasing
Activity

15. So, Li can replace K, Ca, Na, etc.
i.e. Li + NaCl → LiCl + Na
This reaction will occur because Li is
higher on the activity series then Na so
it can replace Na
In the following reaction, no product will
be formed.
Zn + MgO → no reaction
This reaction won’t occur because Zn is
lower on the activity series then Mg so
it’s activity isn’t high enough to replace
Zn

16. Predict whether the following reactions will
occur. If the reaction WILL occur, tell me
the products and balance the equation.
1. Br2 + NaI →
Br2 + 2NaI → 2NaBr + I2
2. Cu(s) + FeSO4 →
Cu(s) + FeSO4 → no reaction
Cu is lower on the activity series then Fe so
no reaction will occur

17. Single Replacement Demo!!!
• Baking soda (sodium bicarbonate)
decomposes upon heating in to solid
sodium carbonate, carbon dioxide gas
and water vapor.
• Equation:

18. Double Replacement
Reactions
“Square Dance”
• Two compounds react to yield two
different compounds (AB + CD  AD +
CB).• The metals and nonmetals of the two
different compounds switch places.
• One of the products must be a solid
precipitate, water, or a gas always!!!!!

19. Skeleton Equation:
Li3PO4 + Zn(NO3)2 → LiNO3 + Zn3(PO4)2
Word Equation:
Lithium phosphate reacts with zinc nitrate to
form lithium nitrate and zinc phosphate.
Balanced Equation
2Li3PO4 + 3Zn(NO3)2 → 6LiNO3 + Zn3(PO4)2

20. Predicting Products
• When given 2 reactants, you should be
able to predict the products.
– Split each compound in to it’s cations and
anions.
– Make new compounds using cations and
anions from the different compounds
• Make sure to criss cross for the new
compounds
– Determine the state of the new
compounds

21. How do you predict the state of the
product????
• Use the solubility rules to find the state
of the products made in either a single or
double replacement reaction.
• Always start by looking at the
anion/negative ion then the
cation/positive ion
– Soluble=aqueous
– Not soluble=solid

22. So, according to our example seen previously,
let’s try to predict the state of the reactants
and products...
Balanced Equation
2Li3PO4 + 3Zn(NO3)2 → 6LiNO3 + Zn3(PO4)2
Balanced Equation with states
2Li3PO4(aq) + 3Zn(NO3)2(aq) → 6LiNO3(aq) +
Zn3(PO4)2(s/ppt)

23. Double Replacement Demo!!!
• Aqueous lead(II) nitrate reacts with
aqueous potassium iodide.
• Equation: