How many molecules are in 15g CH4? How do you figure this out?

Answer 1

The molar mass of CH4 is 16.05 g/mol. You figure this out by adding the molar mass of each atom (Carbon is 12.01g/mol and hydrogen is 1.01g/mol x 4 of them). You then take the 15g and multiply it by the inverse of the molar mass:

15g x 1mol/16.05g = 0.93 mol.