What types of chemical reactions are the following?

Question

Column A
1.
Al + + GaP → Ga + AlP

:
Al + + GaP → Ga + AlP

2.
2 Mg + O2 → 2 MgO

:
2 Mg + O2 → 2 MgO

3.
MgO + BeSe → BeO + MgSe

:
MgO + BeSe → BeO + MgSe

4.
CH4 + 2O2 → CO2 + 2H2O

:
CH4 + 2O2 → CO2 + 2H2O

5.
2 NaCl → Na + Cl2

:
2 NaCl → Na + Cl2

Answer 1

1. Single displacement reaction
2. Combination reaction
3. Double displacement reaction
4. Combustion reaction
5. Decomposition reaction