# What is the empirical formula of a following compound if a sample contain 0.0130 mol C, 0.0390 mol H, and 0.0065 mol O?

So the smallest molar quantity is that of oxgen, $C = \frac{0.0130 \cdot m o l}{0.0065 \cdot m o l}$; $H = \frac{0.0390 \cdot m o l}{0.0065 \cdot m o l}$; $O = \frac{0.0065 \cdot m o l}{0.0065 \cdot m o l}$.
So ${C}_{n} {H}_{m} {O}_{p}$ $=$ ${C}_{2} {H}_{6} O$.