Types of Chemical Reactions
The Matter of Time, Richard Serra, 1994
Reaction types
Evidences of Chemical Reactions
Synthesis Reaction
Two simple reactants react to form one complex product.
A + B → AB
“The relationship”
Ex) 2 H2 + O2 → 2 H2O
→
+
Synthesis Examples
1. H2 + Cl2 →
H2 + Cl2 → 2 HCl
2. Mg + Cl2 →
Mg + Cl2 → MgCl2
3. Al + O2 →
4Al + 3O2 → 2Al2O3
Decomposition Reaction
One complex reactant breaks down into two or more products.
AB → A + B
“The Breakup”
Ex) 2 H2O2 → 2 H2O + O2
+
→
Decomposition Examples
1. H2O →
2 H2O → 2 H2 + O2
2. Na3N →
2 Na3N → 6 Na + N2
3. Al2O3 →
2 Al2O3 → 4 Al + 3 O2
Single Replacement Reaction
An element reacts with a compound to form a new compound and element.
A + BC → AC + B
“The Ol’ Switch-a-Roo”
Ex) Cu + 2AgNO3 → Cu(NO3)2 + 2Ag
🡪
+
+
Single Replacement Examples
1. Fe+ CuSO4 →
Fe+ CuSO4 → FeSO4 + Cu
2. CaI2 + F2 →
CaI2 + F2 → CaF2 + I2
3. NaCl + Mg →
NaCl + Mg → No reaction!
Double Replacement Reaction
Two ionic compounds swap ions to form two new compounds.
AB + CD → AD + CB
“The Double Switch-a-Roo”
Ex) CuNO3(aq) + NaOH(aq) → CuOH (s) + NaNO3(aq)
+
🡪
+
Double Replacement Examples
1. Pb(NO3)2 + K3PO4 →
Pb(NO3)2 + K2PO4 → Pb3(PO4)2 (s) + 2KNO3(aq)
AgNO3 + KCl → AgCl(s) + KNO3(aq)
CaS + AlCl3 → CaCl2(aq) + Al2S3(s)
Combustion
The burning (reaction with O2) of an organic compound (C/H/O compound) to produce CO2 and H2O.
→
+
+
Combustion Examples
1. CH4 + O2 →
CH4 + 2 O2 → CO2 + 2 H2O
2. C3H8 + O2 →
C3H8 + 5 O2 → 3 CO2 + 4 H2O
3. C5H12O3 + O2 →
2 C5H12O3 + 13 O2 → 10 CO2 + 12 H2O