16. a small piece of silver was placed in a solution containing both magnesium nitrate and copper(ii) nitrate.
which one of the following will occur?
a no reaction occurs.
b the silver dissolves and only copper is precipitated.
c the silver dissolves and only magnesium is precipitated.
d a mixture of copper and magnesium forms on the silver.

I believe it's about the dislodging response as Ag structures solvent salt with nitrate. For dislodging response, more receptive metal will uproot less receptive metal from the arrangement. In your question, the reactivity of the metal are positioned as takes after: Mg > Cu > Ag. Take note of that more responsive metals, that are Mg and Cu, are in the arrangement.

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.