Write a net ionic equation for the reaction that occurs when nickel (ii carbonate and excess hydrobromic acid (aq are combined.

First, we write the reaction equation:

NiCO₃ + 2HBr → NiBr₂ + H₂CO₃

Now, writing this in ionic form:

NiCO₃ + 2H⁺ + 2Br⁻ → NiBr₂ + 2H⁺ + CO₃⁻²

(NiCO₃ is insoluble so it does not dissociate in to ions very readily)

Overall equation:

NiCO₃ + 2Br⁻ → NiBr₂ + CO₃⁻²