Write the total ionic and the net ionic equations for the following: 3 H2 (g) + 2 AuCl3 (aq) → 6 HCl (aq) + 2 Au (s)?

"Molecular" equation :
3 H₂(g) + 2 AuCl₃(aq) → 6 HCl(aq) + 2 Au(s)

Total ionic equation :
3 H₂(g) + 2 Au³⁺(aq) + 6Cl⁻(aq) → 6 H⁺(aq) + 6Cl⁻(aq) + 2 Au(s)

Net ionic equation :
3 H₂(g) + 2 Au³⁺(aq) → 6 H⁺(aq) + 2 Au(s)

Ionic and net ionic equations

3H2(g) + 2AuCl3(aq) --> 6HCl(aq) + 2Au(s) ...................... "molecular" equation

3H2(g) + 2Au^3+ + 6Cl- --> 6H+ + 6Cl- + 2Au(s) ................ ionic equation

3H2(g) + 2Au^3+ --> 6H+ + 2Au(s) ...................... ............... net ionic equation

In this reaction, the oxidation number of hydrogen increases from 0 to +1. The oxidation number of gold decreases from +3 to 0

For hydrogen, 2H2 0 →2 H+ 1 + 2 e-
For gold, Au+3 + 3 e- → Au 0

To balance these two equations, we need 3 of the hydrogen reactions and 2 gold reactions. This will require the transfer of 6 electrons

For hydrogen 3 H2 0 → 6 H+ 1 + 6 e-
For gold, 2 Au+3 + 6 e- → 2 Au 0

The chloride ions are called spectator ions, because no electrons are transferred by them.

Total ionic equation = 3 H2 0 + 2 Au+3 → 6 H+ 1+ 2 Au 0