Question

Calculate the empirical formula of compound that contain $26.6\%$ potassium, $35.4\%$ chromium and $38.1\%$ oxygen:

Answer 1

Consider $100gm$ of the compound ,

Moles of $k=\frac{26.6}{3.8}=0.7$

Moles of $Cr=\frac{36.4}{52}=0.68$

Moles of $O=\frac{38.1}{16}=2.38$

$\therefore$ Empirial formula $=K_{0.7}C{r}_{0.68}{O}_{2.38}$

$=K_{2}C{r}_2{O}_7$