The formula of ethanol is C2H6O
From the periodic table:
molar mass of carbon = 12 gm
molar mass of hydrogen = 1 gm
molar mass of oxygen = 16 gm
molar mass of ethanol = 2(12) + 6(1) + 1(16) = 46 gm
number of moles = mass / molar mass = 1.8 / 46 = 0.039 moles
