Question

Assertion :$\left[Cu\right(N{H}_3{)}_4{]}^{2+}$ and $\left[Cu\right(H_{2}O{)}_6{]}^{2+}$ both react with $K_4\left[Fe\right(CN{)}_6]$ to give brown ppt. Reason: Both complexes are blue in colour of little different shade

• A. Assertion is true but the reason is false.
• B. Assertion is false but the reason is true.
• C. Both assertion and reason are true and the reason is a correct explanation of assertion.
• D. Both assertion and reason are true but reason is not a correct explanation of assertion.

Answer 1

The correct option is B Assertion is false but the reason is true.

$\left[Cu\right(N{H}_3{)}_4{]}^{2+}$ and $\left[Cu\right(H_{2}O{)}_6{]}^{2+}$ both do not form precipitate with $K_4\left[Fe\right(CN{)}_6]$. They contain complex ions and retain their identity in the solution
$\left[Cu\right(N{H}_3{)}_4{]}^{2+}$ and $\left[Cu\right(H_{2}O{)}_6{]}^{2+}$ both contain $C{u}^{2+}$ ion. It has $3d^9$ configuration and contains 1 unpaired electrons. Thus both compounds are blue in color.