Question

A hydrocarbon contains 75% of carbon. then its empirical formula is

Answer 1

here is your answer in the attachment hope it helps you

Answer 2

For this kind of problem, you can assume that the weight of the unknown sample is 100g ( since 75%
C
+ 25%
H
= 100%).
Thus,
weight of
C
= 75g
weight of
H
= 25g
Since chemical formulas deal with number of moles rather than weight in grams, you need to convert each element by multiplying it to their respective atomic masses.