Certified Transport Registered Nurse Certification Practice Exam

According to Henry's Law, what is the main factor that affects the solubility of gas in a liquid?

1. Temperature

2. Pressure

3. Volume

4. Altitude

The correct answer is: Pressure

Henry's Law states that the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of that gas above the liquid. This means that as the pressure of the gas increases, more gas molecules will enter into the solution, enhancing solubility. Therefore, pressure is the main factor that affects the solubility of a gas in a liquid, making it the correct answer. In contrast, temperature can also affect gas solubility, but its effect is more complex and varies depending on the specific gas and liquid involved. Generally, increasing temperature tends to decrease gas solubility. Volume does not directly influence gas solubility; it is more relevant in the context of the available space for gas rather than its ability to dissolve in a liquid. Altitude, while it may impact atmospheric pressure and thus indirectly influence gas solubility, is not a primary factor according to Henry's Law.