1. 7.10 Types of reactions Activity
Day Ten
7.10 Types of reactions Activity
Tro's "Introductory Chemistry", Chapter 7

2. Classifying Reactions
One way is based on the process that happens.
Precipitation, neutralization, formation of a gas, or transfer of electrons.

3. Classifying Reactions
Another scheme classifies reactions by what the atoms do.
Type of reaction
General equation
Synthesis
A + B  AB
Decomposition
AB  A + B
Displacement
A + BC  AC + B
Double displacement
AB + CD  AD + CB

4. Tro's "Introductory Chemistry", Chapter 7
Synthesis Reactions
Also known as composition or combination reactions.
Two (or more) reactants combine together to make one product.
Simpler substances combining together.
2 CO + O2 ® 2 CO2
2 Mg + O2 ® 2 MgO
HgI2 + 2 KI ® K2HgI4
Tro's "Introductory Chemistry", Chapter 7

5. Decomposition Reactions
A large molecule is broken apart into smaller molecules or its elements.
Caused by addition of energy into the molecule.
Have only one reactant, make 2 or more products.
Tro's "Introductory Chemistry", Chapter 7

6. Single Displacement Reactions
Reactions that involve one atom displacing another and replacing it in a compound.
Other examples of displacement reactions are:
Fe2O3(s) + Al(s)  Fe(s) + Al2O3(s)
2 Na(s) + 2 H2O(aq)  2 NaOH(aq) + H2(g)
Tro's "Introductory Chemistry", Chapter 7

7. Double Displacement Reactions
Two ionic compounds exchange ions.
X ÅYq (aq) + A ÅBq (aq) ® XB + AY
Precipitation, acid–base, and gas evolving reactions are also double displacement reactions.
Tro's "Introductory Chemistry", Chapter 7

8. Tro's "Introductory Chemistry", Chapter 7
Practice—Classify the Following Reactions as Synthesis, Decomposition, Single Displacement, or Double Displacement.
3 Mg(s) + 2 FeCl3(aq)  3 MgCl2(aq) + 2 Fe(s) CO2(g) + H2O(l)  H2CO3(aq) 3 KOH(aq) + H3PO4(aq)  K3PO4(aq) + 3 H2O(l)
Tro's "Introductory Chemistry", Chapter 7