Answer :
Ethane
C: 2.65 g
H: 0.668 g
1) Divide by the atomic mass of each element
C: 2.65 g / 12.0 g/mol = 0.2208 mol
H: 0.668 g / 1 g/mol = 0.668 mol
2) Divide by the smallest number of moles:
C: 0.2208 / 0.2208 = 1
H: 0.668 / 0.2208 = 3
=> Empirical formula CH3
Acetylene
C: 4.56 g
H: 0.382 g
1) Divide by the atomic mass
C: 4.56 g / 12.0 g/mol = 0.38 mol
H: 0.382 g / 1 g/mol = 0.382 mol
2) Divide by the smallest number
C: 0.38 / 0.38 = 1
H: 0.382 / 0.38 = 1
=> Empirical formula: CH
C: 2.65 g
H: 0.668 g
1) Divide by the atomic mass of each element
C: 2.65 g / 12.0 g/mol = 0.2208 mol
H: 0.668 g / 1 g/mol = 0.668 mol
2) Divide by the smallest number of moles:
C: 0.2208 / 0.2208 = 1
H: 0.668 / 0.2208 = 3
=> Empirical formula CH3
Acetylene
C: 4.56 g
H: 0.382 g
1) Divide by the atomic mass
C: 4.56 g / 12.0 g/mol = 0.38 mol
H: 0.382 g / 1 g/mol = 0.382 mol
2) Divide by the smallest number
C: 0.38 / 0.38 = 1
H: 0.382 / 0.38 = 1
=> Empirical formula: CH