JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
Which of the following \(3 d -m e t a l\) ion will give the lowest enthalpy of hydration \((\Delta_{ hyd } H )\) when dissolved in water?
- A \(Cr ^{2+}\)
- B \(Mn ^{2+}\)
- C \(Fe ^{2+}\)
- D \(Co ^{2+}\)
Answer & Solution
Correct Answer
(B) \(Mn ^{2+}\)
Step-by-step Solution
Detailed explanation
Enthalpy of hydration increases with increase in charge density. \(Mn ^{+2}\) has least charge density (as \(Mn\) has highest size among the given options) so it will have least enthalpy of hydration.
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