1. a How many atoms of the different elements are there in the formulae of the compounds given below?
- (i) nitric acid, HNO3
- (ii) methane, CH4
- (iii) copper nitrate, Cu(NO3)2
- (iv) ethanoic acid, CH3COOH
- (v) sugar, C12H22O11
- (vi) phenol, C6H5OH
- (vii) ammonium sulfate, (NH4)2SO4
2. b Balance the following equations:
- (i) Zn(s) + O2(g) → ZnO(s)
- (ii) Fe(s) + Cl2(g) → FeCl3(s)
- (iii) Li(s) + O2(g) → Li2O(s)
- (iv) H2(g) + O2(g) → H2O(g)
- (v) Mg(s) + CO2(g) → MgO(s) + C(s)