Write the reaction equation: a) Mg → MgO → MgCl2 → Mg (OH) 2 → MgO b) C → CO2 → Na2CO3 → Na2SO4 → BaSO4

а)

1) 2Mg + O2 → 2MgO (compound reaction);

2) MgO + 2HCl → MgCl2 + H2O (exchange reaction);

3) MgCl2 + 2NaOH → Mg (OH) 2 + 2NaCl (exchange reaction);

4) Mg (OH) 2 → MgO + H2O (decomposition reaction).

b)

1) C + O2 → CO2 (compound reaction);

2) CO2 + Na2O → Na2CO3 (compound reaction);

3) Na2CO3 + H2SO4 → Na2SO4 + H2O + CO2 (exchange reaction);

4) Na2SO4 + BaCl2 → BaSO4 ↓ + 2NaCl (exchange reaction).