The temperature at which vaporization takes place is:
a. High temperature
b. Constant temperature
c. Saturation temperature
d. None of the above.
The correct answer and explanation is:
The correct answer is: c. Saturation temperature.
Explanation:
Vaporization is the phase transition from a liquid to a gas, and it occurs when the molecules in the liquid have enough energy to overcome the forces holding them together. This process happens at the saturation temperature, which is the temperature at which a liquid turns into a vapor at a given pressure.
At the saturation temperature, the liquid and its vapor coexist in equilibrium. For example, the boiling point of water at sea level is 100°C, and at this temperature, the vapor pressure of the water is equal to the atmospheric pressure, allowing the liquid to transition into gas. This temperature varies with pressure: as pressure increases, the saturation temperature also increases, and as pressure decreases, the saturation temperature decreases.
The term vaporization encompasses two processes: evaporation and boiling. Evaporation occurs at the surface of the liquid at temperatures below the boiling point, while boiling involves the entire liquid undergoing vaporization at the saturation temperature. The saturation temperature corresponds to the boiling point under specific conditions, like atmospheric pressure.
In general, vaporization occurs at a constant temperature during a phase change because the energy supplied is used to break the intermolecular bonds in the liquid rather than increasing the temperature. Once the liquid reaches the saturation temperature, the energy supplied continues to be used for the phase change, turning the liquid into a gas.
Thus, the temperature at which vaporization occurs is directly related to the saturation temperature of the substance at a given pressure.