Give the complete ionic equation for the reaction (if any) that occurs when aqueous solutions of mgso3 and hi are mixed.

We are asked to give the equation of the raction of aqueous solutions of MgSO3 and HI. In this case,the type of reaction involving these two reactants is double replacement or substitution where the places of the cations are exchanged in the products side. The equation thus is expressed:
MgSO3(aq) + 2HI(aq) → MgI2(aq) + SO2(g) + H2O(l)

They carry out the exchange of gases as we breathe ( oxygen and carbon dioxide).