1. double replacement[two of the chemical species(B and D)exchanged positions]
2. Combustion(the reaction with oxygen produced CO2 and water; products of Combustion)
3. Single replacement(only one chemical specie[B] exchanged position)
4. Combination(the two reactants formed a single product)
5. Decomposition(a compound released two constituent products)
6. 1PbCl2 + 2AgNO3 = 1Pb(NO3)2 + 2AgCl. it is a double replacement reaction since two chemical species(Chlorine(Cl) and Nitrogen(iii)oxide[NO3]) exchanged positions.
7. 1NH3 + HCL = NH4Cl. it is a combination reaction since two reactants formed a single product.
8. 2AlCl3 + 3Na2SO4 = 1Al(SO4)3 + 6NaCl. it is a double replacement reaction since two chemical species(chlorine[Cl] and sulphate[SO4]) exchanged positions.
9. 1Zn + 1S = 1ZnS. it is a combination reaction since two reactants formed a single product.
10. 1Al2(SO4)3 + 3BACl2 = 3BASO4 + 2ALCL3. it is a double replacement reaction since two chemical species(chlorine[Cl] and sulphate[SO4]) exchanged positions.
11. 1Al2S3 = 2Al + 3S. it is a decomposition reaction since a reactant released two constituent products.
12. 1H2SO4 + 1Fe = 1H2 + 1FeSO4. it is a single replacement reaction since one chemical specie(sulphate[SO4]) exchanged position.
13. C12H22O11 + 12O2 = 12CO2 + 11H2O. it is a combustion reaction since a reactant combined with oxygen to release carbon dioxide(CO2) and water(H2O).
14. 1Mg(OH)2 + 1H2SO4 = 1MgSO4 + 2H2O. it is a double replacement reaction since two chemical species(hydroxide[OH] and sulphate[SO4]) exchanged positions.
15. 2NaOH + 1CuSO4 = Na2SO4 + Cu(OH)2. it is a double replacement reaction since two chemical species(hydroxide[OH] and sulphate[SO4]) exchanged positions.
16. 1C4H12 + 7O2 = 6H2O + 4CO2. it is a combustion reaction since a reactant combined with oxygen to release carbon dioxide(CO2) and water(H2O).
17. 4Fe + 3O2 = 2Fe2O3. it is a combination reaction since two reactants formed a single product.
18. 1Mg3(PO4)2 + 3H2 = 3Mg + 2H3PO4. it is a single replacement reaction since one chemical specie(phosphate[PO4]) exchanged position.
19. 2NH4NO3 = 2N2O + 4H2O. it is a decomposition reaction since a reactant released two constituent products.
20. 1Cl2 + 2KBr = 2KCl + 1Br2. it is a single replacement reaction since one chemical specie(potassium[K]) exchanged position.