Q33 / 150 · MHT CET 2012 · Chemistry
The oxidation state of $\mathrm{Cr}$ in $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ is
- A$+4$
- B$+3$
- Correct answerC$+6$
- D$+5$
Solution
$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$
Let the oxidation state of $\mathrm{Cr}$ is $x$.
$$
\begin{aligned}
2(+1)+2 x+7(-2) &=0 \\
+2+2 x-14 &=0 \\
2 x-12 &=0 \\
x &=+6
\end{aligned}
$$
Hence, the correct answer is option: 'C'.