Question

the pressure and temperature at which there is no longer a difference between liquid and gas is called
a. critical mass
b. point of vaporization
c. critical point
d. point of saturation

Explanation:

The critical point is defined as the specific pressure and temperature where the liquid and gas phases of a substance become indistinguishable, matching the description in the question. Critical mass refers to the amount of fissile material needed for a chain reaction, vaporization point is when liquid turns to gas, and saturation point is when a solution can't dissolve more solute, so these are incorrect.

Answer:

C. Critical point.