Question

A balloon contains 2.0 g of hydrogen gas. A second balloon contains 4.0 g of helium gas. Both balloons are at the same temperature and pressure. Pick the false statement from the following list.

• A. The number of hydrogen molecules is the same as the number of helium atoms in each balloon
• B. The density of the helium in its balloon is greater than the density of the hydrogen in its balloon
• C. The volume of each balloon is the same
• D. The average speed of the molecules/atoms in each balloon is the same

Hint:

At the same temperature and pressure, gases with the same volume have the same number of molecules, but the masses and volumes differ based on the molar mass of the gases.

Answer 1

The Correct Option is C

According to the ideal gas law, at the same temperature and pressure, the volume of gas is proportional to the number of moles. Since the number of moles of hydrogen (\(2.0 \, {g} \)) and helium (\(4.0 \, {g}\)) differ, the volumes of the balloons must be different. Therefore, statement (c) is false.