Question

6. A sample of a gas has a mass of 0.527 g. Its volume is 0.35 L at a temperature of 88 degree Celsius and a pressure of 945 mm Hg. Find it's molar mass (show your work)

Answer 1

Answer: The molar mass of the gas is 35.87 g/mol.

Explanation:

To calculate the mass of gas, we use the equation given by ideal gas:

PV = nRT

or,

$PV=\frac{m}{M}RT$

where,

P = Pressure of gas = 945 mmHg

V = Volume of the gas = 0.35 L

m = Mass of gas = 0.527 g

M = Molar mass of gas = ? g/mo

R = Gas constant = $62.3637\text{ L.mmHg }mol^{-1}K^{-1}$

T = Temperature of gas =  $88^oC=[88+273]=361K$

Putting values in above equation, we get:

$945mmHg\times 0.35L=\frac{0.527g}{M}\times 62.3637\text{ L.mmHg }mol^{-1}K^{-1}\times 361K\\\\M=35.87g/mol$

Hence, the molar mass of the gas is 35.87 g/mol.