Question

"If an unknown compound is found to have an empirical formula of CH4, which of the following is the molecular formula if the molar mass was determined to be 128 g/mol?

A. CH₄
B. CH₁₂
C. C₈H₁₂
D. C₈H₃₂
E. C₁₂H₁₆"

Answer 1

The molecular formula of the compound with an empirical formula of CH4 and a molar mass of 128 g/mol is C8H32.

Step-by-step explanation:

The empirical formula of a compound represents the simplest whole number ratio of atoms in the compound. To determine the molecular formula, we need to know the molar mass of the compound. In this case, the empirical formula is CH4 and the molar mass is 128 g/mol.

The molar mass of the empirical formula CH4 is 16 g/mol (1 carbon atom + 4 hydrogen atoms). To find the molecular formula, we divide the molar mass of the compound (128 g/mol) by the molar mass of the empirical formula (16 g/mol). This gives us a multiple of 8.

Multiplying the empirical formula CH4 by 8 gives us the molecular formula C8H32. Therefore, the answer is D. C8H32.