Question

Mg---> MgO---> MgCL2---> Mg(OH)2
                                           ↓
                                         MgO
                                           

Answer 1

Mg → MgO → MgCl₂ → Mg(OH)₂ → MgO.

2Mg + O₂ = 2MgO
2Mg⁰ + O₂ = 2MgO

MgO + 2HCl = MgCl₂ + H₂O;
MgO + 2H⁺ + 2Cl⁻ = Mg²⁺ + 2Cl⁻ + H₂O;
MgO + 2H⁺ = Mg²⁺ + H₂O.

MgCl₂ + 2NaOH = Mg(OH)₂↓ + 2NaCl;
Mg²⁺ + 2Cl⁻ + 2Na⁺ + 2OH⁻ = Mg(OH)₂↓ + 2Na⁺ + 2Cl⁻;
Mg²⁺ + 2OH⁻ = Mg(OH)₂↓.

Mg(OH)₂ → (t°) MgO + H₂O.