Question

HELP!!!!!What is the molar mass of a gas which has a density of .249 g/L at 20.0 degrees Celsius and a pressure of .95 atm?

Answer 1

Answer:

6.31g/mol

Explanation:

Using the ideal gas equation;

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas law constant (0.0821 Latm/molK)

T = temperature (K)

Mole (n) = mass (m)/molar mass (Mm)

* Mm = m/n

Also, density (p) = mass (m) ÷ volume (V)

PV = nRT

Since n = M/Mm

PV = M/Mm. RT

PV × Mm = m × RT

Divide both sides by V

P × Mm = m/V × RT

Since p = m/V

P × Mm = p × RT

Mm = p × RT/P

Mm = 0.249 × 0.0821 × 293/0.95

Mm = 5.989 ÷ 0.95

Mm = 6.31g/mol