The density of an unknown gas at 320K is 3.97 g/L and exerts a pressure of 1.80 atm in a cylinder.What is the gas? A) F₂ B) C₄H₁₀ C) Cl₂ D) C₂H₂

Question

Quizplus · Accepted Answer

Using the ideal gas law, PV=nRT, we can calculate the molar mass of the gas.

n/V = P/RT

n/V = (1.80 atm)/(0.08206 L·atm/mol·K × 320 K)

n/V = 0.0694 mol/L

We can then calculate the molar mass:

molar mass = (3.97 g/L) / (0.0694 mol/L) = 57.2 g/mol

Looking at the answer choices, only choice B has a gas with a molar mass close to 57.2 g/mol: carbon tetrachloride (CCl4).

The Density of an Unknown Gas at 320K Is 3