MCQ
The oxidation number of $Cr$ in ${K_2}C{r_2}{O_7}$ is
- ✓$+6$
- B$-7$
- C$+2$
- D$-2$
✓
Answer
Correct option: A.
$+6$
(a) $\mathop {{K_2}C{r_2}{O_7}}\limits^{ * \,\,} $
$2 + 2x - 2 \times 7 = 0$; $2x - 14 + 2 = 0$
$2x = 12$; $x = \frac{{12}}{2} = + 6$.
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