Question

which statement(s) is/are true for a liquid that is evaporating? select all that apply a vapor pressure < atmospheric pressure b vapor pressure = atmospheric pressure c bubbles can form. d bubbles cannot form.

Explanation:

Step1: Recall boiling and evaporation concepts

Evaporation occurs at the surface of a liquid. Boiling occurs when vapor pressure equals atmospheric pressure and bubbles form. Evaporation does not require vapor pressure to equal atmospheric pressure.

Step2: Analyze each option

• Option a: For evaporation, vapor pressure is less than atmospheric pressure. This is correct as evaporation is a surface - level phenomenon and does not require the liquid to reach a state where vapor pressure equals atmospheric pressure (which is for boiling).
• Option b: Vapor pressure = atmospheric pressure is the condition for boiling, not evaporation. So this is incorrect.
• Option c: Bubbles form during boiling (when vapor pressure = atmospheric pressure). Since evaporation is not boiling, bubbles do not form. So this is incorrect.
• Option d: Since evaporation is a surface - level process (not bulk like boiling), bubbles cannot form. This is correct.

Answer:

A. vapor pressure < atmospheric pressure, D. Bubbles cannot form.