How do you account for the strong reducing power of lithium in aqueous solution?

Explanation

Electrode potential is a measure of the tendency of an element to lose electrons in the aqueous solution . It mainly depends upon the following three factors , i.e.,
(i) `Li (s) overset("Sublimation enthalpy")(to) Li (g) , (ii) Li (g) overset("Ionization enthalpy")(to) Li^(+) (g)`
(iii) `Li^(+) (g) + aq to Li^(+) (aq) + ` enthalpy of hydration
The sublimation enthalpy of alkali metals are almost similar . since Li has the smallest size , its enthalpy of hydration is the highest among alkali metals . Although ionization enthalpy of Li is the highest among alkali metals , it is more than compensated by the high enthalpy of hydration . Thus , Li has the most negative standard electrode potential `(-3*04 V)` and hence Li is the strongest reducing agent in aqueous solution mainly because of its high enthalpy of hydration .