Question

Which compound is zero valent metal complex ?

• A. $[Cu(NH_3]_4]SO_4$
• B. $[Pt(NH_3)_2Cl_2]$
• C. $[Ni(C0)_4]$
• D. $K_3 [Fe (CN)_6]$

Answer 1

Answer: (C)

$[Ni(C0)_4]$

Answer 2

$\left[ Cu ( NH )_{4}\right] SO _{4}$

Oxidation numbers of

$Cu \Rightarrow x+4 \times 0-2 =0$
$x-2 =0$
$x =+2$

Oxidation number of $Cu =+2$

Oxidation number of $Pt$ in $\left[ Pt \left( NH _{3}\right)_{2} Cl _{2}\right]$
$x+2 \times 0+2 \times-1 =0$
$x-2 =0$
$x =+2$

Oxidation number of $Ni$ in $\left[ Ni ( CO )_{4}\right]$
$x+4 \times 0=0$
$x=0$

Oxidation number of Fe in $K _{3}\left[ Fe ( CN )_{6}\right]$
$3 \times(+1)+x+6 \times-1 =0$
$3+x-6 =0$
$x =+3$
$\therefore\left[ Ni ( CO )_{4}\right]$ is zero valent compound