Question

Among the following complexes, the one that has highest enthalpy of hydration is

• A. $\left[Co\left(H_{2}O\right)_{6}\right]^{2+}$
• B. $\left[Mn\left(H_{2}O\right)_{6}\right]^{2+}$
• C. $\left[V\left(H_{2}O\right)_{6}\right]^{2+}$
• D. $\left[Cr\left(H_{2}O\right)_{6}\right]^{2+}$

Answer 1

Answer: (C)

$\left[V\left(H_{2}O\right)_{6}\right]^{2+}$ has $V^{2+}$ metal having $3d^{3}$ electronic configuration due to which it has maximum negative value of $CFSE$ out of all. Hence, has maximum enthalpy of hydration.