Question

The density of a gas at 30°C and 1.3 atmosphere pressure is 0.027 g/cc. Calculate the molecular weight of the gas.

Answer 1

According to the ideal gas equation,

                                         PV = nRT

From the given,

Pressure = 1.3 atm

Volume = ?

T = 303 K

R = 0.082057 L-atm/mol.K

                   $V\quad =\quad \frac { nRT }{ P }$

                   $=\quad \frac { 1.3\quad \times \quad 0.0820\quad \times \quad 303\quad  }{ 1.3 } \quad =\quad 24.8$

Therefore, that we need 24.8 L of gas to get one mole.

Therefore, molar mass of gas $= 24.8\times 2.7\quad =\quad 67\quad g/mole$

Answer 2

MOLAR MASS OF THE GAS IS 67g/mole