Vaporization can be increased by which action on a liquid?

Vaporization can be increased by which action on a liquid?

• A. Reducing the pressure on the liquid
• B. Increasing the pressure on the liquid
• C. Maintaining the pressure on the liquid
• D. Fluctuating the pressure on the liquid

Answer: (A)

Vaporization increases when the external pressure on a liquid is reduced because lower pressure lowers the energy barrier for molecules to escape into the vapor phase. When pressure drops, the liquid’s boiling point decreases, so at a given temperature the liquid can begin to boil and turn into vapor more readily. Pushing pressure up has the opposite effect, raising the boiling point and making vaporization harder. In practical terms, reducing pressure in a system—such as in an evaporator—allows the refrigerant to boil and absorb heat efficiently.

Vaporization increases when the external pressure on a liquid is reduced because lower pressure lowers the energy barrier for molecules to escape into the vapor phase. When pressure drops, the liquid’s boiling point decreases, so at a given temperature the liquid can begin to boil and turn into vapor more readily. Pushing pressure up has the opposite effect, raising the boiling point and making vaporization harder. In practical terms, reducing pressure in a system—such as in an evaporator—allows the refrigerant to boil and absorb heat efficiently.