Question

Write chemical equations for the following. Indiciate physical states and write net ionic equations. If there is no reaction indicate so.

a) ammonium phosphate + magnesium sulfate

b)Potassium carbonate + ammonium chloride

c) magnesium + acetic acid.

Answer 1

1)

2(NH₄)₃PO_4(aq) + 3MgSO_4(aq) ---> 3(NH₄)₂SO_4(aq) + Mg₃(PO₄)_2(s)

_{Net ionic equation :}

(NH₄)₃PO_4(aq) -----> 3 NH₄⁺_(aq) + PO₄^3-_(aq)

MgSO₄ ----> Mg⁺²_(aq) + SO₄^-2_(aq)

Combining above equations :

6NH₄⁺_(aq) + 2PO₄^3-_(aq) + 3Mg⁺²_(aq) + 3SO₄^-2_(aq) ----> Mg₃(PO₄)_2(s) + 6NH₄⁺_(aq) + 3SO₄^-2_(aq)

Net ionic equation :

3Mg⁺²_(aq) + 2PO₄^3-_(aq) ---> Mg₃(PO₄)_2(s)

Remaining ions are spectator ions which donot involve in reaction

2) K₂CO_3(aq) + 2NH₄Cl_(aq) ------> 2KCl_(aq) + NH_3(g) + CO_2(aq) +H₂O_(l)

K₂CO_3(aq) -------> 2K⁺_(aq) + CO₃^2-_(aq)

NH₄Cl_(aq) ----> NH₄⁺_(aq) + Cl^-_(aq)

Ionic equation :

2K⁺_(aq) + CO₃^2-_(aq) + NH₄⁺_(aq) + Cl^-_(aq) ---> 2K⁺_(aq) + CO_2(g) + NH_3(aq)+H₂O_(l) + Cl^-_(aq)

Net ionic equation :

CO₃^2-_(aq) + NH₄⁺_(aq) -----> NH_3(aq) + CO_2(g)+H₂O_(l)

Remaining ions are spectator ions which donot involve in reaction

3) Mg_(s) + 2CH₃COOH_(aq) -----> Mg(CH₃COO^-)_2aq + H_2(g)

2CH₃COOH_(aq) -----> CH₃COO^-_(aq) + 2H⁺_(g)

Mg_(s) ----> Mg⁺²_(aq)

Ionic equation :

Mg_(s) + 2CH₃COO^-_(aq) +2H⁺_(aq) -----> 2CH₃COO^-_(aq) + Mg⁺²_(aq) + H_2(g)

Net ionic equation

Mg_(s) + 2H⁺_(aq) ------> Mg⁺²_(aq) + H_2(g)

Acetic acid is a weak acid and cannot dissociate completely so acetate ions are spectator ions