how many grams of carbon are contained in 1.00 mol of c2h6?
Since we know the atomic masses of the elements, we can sum the atomic masses to obtain the molecular masses. We also know that 1 mole of C atoms weighs 12.01 g and 1 mol of H atoms weighs 1.0079 g. So, we know the molar mass of ethane also. Or, 30.07 g in 1 mole C2H6.