2. (a).Define the following terms:

(i).Valency                                             (ii).Atom

 (iii).Radical                                           (iv).Molecule


(b). Using symbols, valency of radical and elements, write the chemical formulae for the following compounds:

1. Iron (II) sulphate                  

2.iron (III) sulphate

3. Calcium nitrate                     

4.Aluminium sulphate

5. Ammonium phosphate         

6. Aluminium oxide

7. Lead nitrate                          

8. Potassium carbonate

9. Calcium hydrogen carbonate

10. Magnesium nitride

11. Sodium oxide                      

12. Calcium phosphate

13. Sodium hydrogen sulphate

14. Aluminium chloride

15. Calcium hydroxide            

16. Sodium sulphite

17. Carbon dioxide                  

18. Sodium sulphate

 (c).Give the chemical names for the following compounds:

(i).Cu(NO3)2                                        (ii).AlCl3

 (iii).Fe(OH)3(iv)                                  (iv).Mg(HCO3)2                                   

(v).NaOH                                            (vi). CO

 (vii).SO2                                             (viii).H2SO4

 (ix). (NH4)2CO3                                  (x).AgCl

Complete and balance the following equations: