Which of the following has the highest tendency to give the reaction.Mg+→mediumaqueousMaq.+

Mg+→mediumaqueousMaq.+Lig+  has the highest tendency to give the Liaq.+Reason:Li+ ion is smaller in size, and hence it possess greater nuclear charge, so attraction of water molecules by Li+ ion increases, therefore degree of hydration increases, and hence hydraction energy increases. It is a Exothermic processNOTE :The amount of energy released during the hydration of 1mole of ions is called hydration energyStability of  Maq+ ∝ hydraction energy