A compound contains 75% carbon and 25% hydrogen by mass. What is the empirical formula for this compound?
CH
C4H
CH4
C2H8

The empirical formula would be CH4.

“To get the empirical formula of the compound, we convert each mass percentage to mole percentage by dividing each to corresponding molar mass. 75% mass of carbon is 6.25 while 25% hydrogen is 25. We divide 25 by 6.25, we get 4. Hence, the empirical formula is CH4.”

Yes i think so not 100 percent sure though