Question

A 0.5 mol sample of helium (He) and a 0.5 mol sample of neon (Ne) are placed separately into 10 liter rigid containers at 25°C. Each container has a pinhole opening. Which of the gases, helium (He) or neon (Ne), will escape faster through the pinhole and why?

Answer 1

Helium will escape faster than neon through the pinhole due to its lower molar mass, in accordance to Graham's law of effusion.

Step-by-step explanation:

The student's question is about comparing the rate at which helium (He) and neon (Ne) will escape through a pinhole in 10 liter rigid containers at 25°C. According to Graham's law of effusion, the rate of effusion of a gas is inversely proportional to the square root of its molar mass. Helium, with a molar mass of 4.00 g/mol, will effuse faster than neon, which has a molar mass of 20.18 g/mol. This is because lighter gases effuse more quickly than heavier gases through small openings such as pinholes.

Therefore, helium will escape faster than neon from the containers through the pinhole. This concept is further illustrated by the difference in the behavior of helium and ethylene oxide, where ethylene oxide being much heavier with a molar mass of 44.0 g/mol effuses at a significantly slower rate than helium.