Question

The oxidation states of $Cr$ in $[Cr(H_{2}O{)}_6]C{l}_3,[Cr(C_6{H}_6{)}_2]$, and $K_2[Cr(CN{)}_2(O{)}_2(O_2)(N{H}_3)]$ respectively are :

• A. +3, +4, and +6
• B. +3, +2, and +4
• C. +3, 0, and +6
• D. +3, 0, and +4

Answer 1

Answer: (C)

$\left[Cr{\left(H_{2}O\right)}_6\right]C{l}_3$

$\Rightarrow x+0\times 6-1\times 3=0$

$\therefore x=+3$

$\left[Cr{\left(C_6{H}_6\right)}_2\right]$

$\Rightarrow x+2\times 0=0$

$x=0$

$K_2[Cr(CN{)}_2\left(O_2\right)\left(O_2\right)N{H}_3]$

$\Rightarrow 1\times 2+x-1\times 2-2\times 2-2\times 1=0$

$\Rightarrow x-6=0$

$x=+6$