Explanation:
The formula used :
[tex]PM=dRT[/tex]
Where:
P = pressure of the gas
M = Molar mass of the gas
d = Density of the gas
T = temperature of the gas
R = Universal gas constant = 0.0821 atm L/mol K
A.
The density of the gas at STP, d = 1.25 g/L
Pressure of the gas = 1 atm
Temperature of the gas = T = 273 K
[tex]M=\frac{dRT}{P}=\frac{1.25 g/L\times 0.0821 atm l/mol k\times 273 K}{1 atm}[/tex]
M = 28.01 g/mol
Molar mass of nitrogen gas =28 g/mol ≈ 28.01 g/mol
The density of nitrogen gas at STP is 1.25 g/L.
B.
The density of the gas at STP, d = 2.86 g/L
Pressure of the gas = 1 atm
Temperature of the gas = T = 273 K
[tex]M=\frac{dRT}{P}=\frac{2.86g/L\times 0.0821 atm l/mol k\times 273 K}{1 atm}[/tex]
M = 64.10 g/mol
Molar mass of sulfur dioxide gas = 64g/mol ≈ 64.10 g/mol
The density of sulfur dioxide gas at STP is 2.86 g/L.
C.
The density of the gas at STP, d = 0.714 g/L
Pressure of the gas = 1 atm
Temperature of the gas = T = 273 K
[tex]M=\frac{dRT}{P}=\frac{0.714 g/L\times 0.0821 atm l/mol k\times 273 K}{1 atm}[/tex]
M = 16.00 g/mol
Molar mass of methane gas = 16 g/mol
The density of methane gas at STP is 0.714 g/L.
