Question

Which of the following order is correct with respect to the hydration enthalpy?

(a) B > Mg > Ca < Sr > Ba

(b) Be^+2 > Mg^+2 > Ca^+2 > Sr^+2 > Ba^+2

(c) B > Mg < Ca > Sr > Ba

(d) B > Mg > Ca > Sr < Ba

The question was asked by my school principal while I was bunking the class.

Asked question is from s-Block Elements topic in division s-Block Elements of Chemistry – Class 11

Answer 1

The correct answer is (b) Be^+2 > Mg^+2 > Ca^+2 > Sr^+2 > Ba^+2

The best explanation: The hydration enthalpy decreases with the increase in ionic size along with the group towards down, the correct order of hydration enthalpy is given as Be^+2 > Mg^+2 > Ca^+2 > Sr^+2 > Ba^+2 and the hydration enthalpies of alkaline earth metal ions are greater than the size of alkali metal ions. We can say that these are extensively hydrated than them.