The mass of 11.2 litres of a certain gas at s.t.p. is 24 g. Find the gram molecular mass of the gas.

Calculate :

(i) The number of moles in 12 g. of oxygen gas. [O = 16]

(ii) The weight of 10²² atoms of carbon.

[C = 12, Avogadro's No. = 6 x 10²³]

Calculate the number of molecules in 4.4 gm. of CO₂

[C = 12, O = 16]

Fill in the blank from the choices given in bracket : The number of moles in 11 g. of nitrogen gas is …………… [0.39, 0.49, 0.29] [N = 14]