What reaction might we use to synthesize nickel sulfate, NiSO4?

Write equations for acid-base neutralization. Include states in your answer.

Write equations of acid with carbonate. Include states in your answer.

As I understand from your question, we should synthesize nickel sulfate first from nickel (II) oxide and sulfuric acid and second from nickel carbonate and sulfuric acid.

The chemical reactions will look like this:

NiO (s) + H₂SO₄ (aq) → NiSO₄ (aq) + H₂O (l)

NiCO₃ (aq) * + H₂SO₄ → NiSO₄ (aq) + H₂CO₃ (aq)

but carbonic acid will decompose to carbon dioxide and water

H₂CO₃ (aq) → CO₂ (g) + H₂O (l)

(*) NiCO₃ has a poor solubility in water, but enough to start the reaction.