A Gas Consists of 85 $\degree$ C Calculate Its Empirical and Molecular Formulas

Multiple Choice

A gas consists of 85.7 % carbon and 14.3% hydrogen, by weight. A sample of this gas weighing 0.673 g occupies 729 mL at a pressure of 720.0 mmHg and a temperature of 77 $\degree$ C. Calculate its empirical and molecular formulas.

A) CH, C₂H₂
B) CH₂, C₂H₄
C) CH₂, C₃H₆
D) CH₃, C₂H₆
E) CH₄, CH₄