Question

Oxidation number of chromium in potassium dichromate is:

• A. 4
• B. 5
• C. 6
• D. 3

Answer 1

Answer: (C)

6

Let $x$ be the oxidation state of $Cr$ in $K_{2}C{r}_2{O}_7$.

For a neutral compound, the sum of oxidation states of all elements is equal to zero.

Therefore, $+2+2x-14=0$

or, $x$ $=$ $+6$

Hence, the oxidation state of Cr is $+6$.