Certified Transport Registered Nurse Certification Practice Exam

What does Henry's Law state about gases dissolved in liquids?

1. Volume is proportional to temperature

2. Weight of a gas dissolved is proportional to the weight of gas above it

3. Rate of effusion is inversely proportional to molecular weight

4. Pressure is directly proportional to volume

The correct answer is: Weight of a gas dissolved is proportional to the weight of gas above it

Henry's Law describes the relationship between the concentration of a gas dissolved in a liquid and the pressure of that gas above the liquid. Specifically, it states that at a constant temperature, the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of that gas in equilibrium with the liquid. This concept means that if the pressure of the gas above the liquid increases, more of the gas will dissolve into the liquid. Therefore, the correct choice emphasizes this relationship by indicating that the weight of a gas dissolved in a liquid is proportional to the weight of the gas that is present above it. This understanding is crucial for applications such as calculating gas concentrations in medical and environmental settings. The other options focus on different gas laws or principles that do not pertain specifically to Henry's Law. For example, the relationships regarding volume and temperature, as well as the inverse relationship between the rate of effusion and molecular weight, pertain to different concepts in gas behavior. Pressure-volume relationships are addressed by Boyle's Law instead, making them unrelated to the specifics of Henry's Law.