Question

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

Answer 1

75% Carbon
25% hydrogen

molar mass C and H is:

12.0 g/ mol
1.0 g/mol

number of moles:

C = 75 / 12 => 6.25 moles
H = 25 / 1 => 25 moles

C = 6.25 / 6.25 => 1
H = 25 /6.25 => 4

the empirical formula is: CH₄

hope this helps!