IIT-JEE 2008 · Paper 2 · Chemistry Q48

ChemistrySingle correct+3 / -1Question 48 of 66

Among the following, the coloured compound is

CuCl

\ce{K3[Cu(CN)4]}

\ce{CuF2}

\ce{[Cu(CH3CN)4]BF4}

Answer and worked solution

Official answer: C

CuCl, $\ce{K3[Cu(CN)4]}$ and $\ce{[Cu(CH3CN)4]BF4}$ all contain Cu(I), $3d^{10}$ : no d-d transitions, colourless.
$\ce{CuF2}$ contains Cu(II), $3d^9$ , with d-d transitions: coloured.

(C)

IIT-JEE 2008 · Paper 2, Chemistry question 48