Help pleaseee find the molecular formula of a compound with a molar mass of 70.0 g/mol and an empirical formula of CH2.

In order to find the molecular formula from an empirical formula you must find the ratio of their molecular masses.

We know that the molecular mass of the molecule is 70

gmol-1

. We can calculate the molar mass of

CH2

from the periodic table:

C=12.01

gmol−1

H=1.01

gmol−1

CH2 =14.03

gmol−1

Hence we can find the ratio:

14.03

70

≈

0.2

answer carbon and three oxygen atoms;