# What is the charge on the chromium ion in the ionic compound that has the formula Cr_2O_3?

Jun 28, 2017

+3

#### Explanation:

A compound has a zero net charge. so

$2 \times C r + 3 \times O = 0$

Oxygen O almost always has a charge of -2 so

$2 \times C r + 3 \times \left(- 2\right) = 0$

$2 \times C r + - 6 = 0$ add + 6 to both sides

$2 \times C r + - 6 + 6 = 0 + 6$ so

$2 \times C r = + 6$ divide both side by 2

$\frac{2}{2} \times C r = + \frac{6}{2}$ equals

$C r = + 3$