The molecular formular of a hydrocarbon with an empirical formula of CH3 and a molar mass of 30 is
Answer Details
To find the molecular formula of a hydrocarbon given its empirical formula and molar mass, you need to compare the empirical formula mass with the given molar mass.
The empirical formula given is CH3. The molar mass of the empirical formula is calculated as follows:
Carbon (C): 1 atom × 12 g/mol = 12 g/mol
Hydrogen (H): 3 atoms × 1 g/mol = 3 g/mol
Total empirical formula mass = 12 + 3 = 15 g/mol
The provided molar mass of the compound is 30 g/mol. To determine how many empirical units are in the molecular formula, divide the molecular mass (given) by the empirical formula mass:
Number of empirical units = 30 g/mol / 15 g/mol = 2
Therefore, the molecular formula is twice the empirical formula: