What is the mass of 56 cm3 of carbon monoxide at S.T.P.?
(C = 12, O = 16)
22400 cm3 of CO has mass = 12 + 16 = 28 g
∴ 56 cm3 will have mass = 2822400\dfrac{28}{22400}2240028 x 56 = 0.07 g
