Answer
Empirical formula $C_2S$
Molecular formula: $C_{16}S_8$
Work Step by Step
Atomic weights (g/mol): $C: 12.011,\ S: 32.06$
In 100.0 g:
C: $42.83\ g \div 12.011 = 3.566\ mol$
S: $57.17\ g\div 32.06= 1.783\ mol$
Normalizing by the smallest amount of moles:
S: $1.783/1.783 = 1.0$
C: $3.566/1.783= 2.0$
Empirical formula $C_2S$
Empirical formula's molar mass: $M_u=56.09\ g/mol$
$M/M_u=8.0$
Molecular formula: $C_{16}S_8$
