Question

The order of colours exhibited by Cr${}^{+2}$, Cr${}^{+3}$ and Cr${}^{+6}$ ions are respectively :

• A. green, blue, yellow
• B. blue, green, yellow
• C. yellow, blue, green
• D. blue, yellow, green

Answer 1

The correct option is B blue, green, yellow

$C{r}^{2+}$ ions gives blue color on flame test.

$C{r}^{3+}$ ions gives green color on flame test.

$C{r}^{6+}$ ions gives yellow color on flame test.

Hence option B is correct.