Answer : The mass of
gas is, 4477.8 g
Solution :
using ideal gas equation,

where,
n = number of moles of gas
w = mass of gas
P = pressure of the gas = 
conversion : 
T = temperature of the gas = 
M = molar mass of
gas = 28 g/mole
R = gas constant = 0.0821 Latm/moleK
V = volume of gas = 20 L
Now put all the given values in the above equation, we get the mass of gas.


Therefore, the mass of
gas is, 4477.8 g