Question

under which conditions would the solubility of a gas be greatest?
○ high pressure and high temperature
○ high pressure and low temperature
○ low pressure and high temperature
○ low pressure and low temperature

Explanation:

1. Effect of Pressure on Gas Solubility: According to Henry's Law, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid. So, higher pressure (more gas molecules above the liquid) forces more gas molecules into the liquid, increasing solubility.
2. Effect of Temperature on Gas Solubility: Gas dissolving in a liquid is usually an exothermic process (releases heat, like \( \text{gas} + \text{liquid}

ightleftharpoons \text{solution} + \text{heat} \)). Using Le Chatelier's principle, lowering the temperature (removing heat) shifts the equilibrium to the right (toward the solution), increasing solubility. High temperature provides energy for gas molecules to escape the liquid, decreasing solubility.

1. Combining Effects: High pressure (to push gas into liquid) and low temperature (to favor dissolution equilibrium) together maximize gas solubility. Other options: High temp (decreases solubility) or low pressure (decreases solubility) in their combinations don't favor high solubility.

Answer:

B. high pressure and low temperature