New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    What happens to a liquid, when the vapour pressure

    equals the atmospheric pressure?
    A The liquid cools Correct Answer Incorrect Answer
    B The liquid boils Correct Answer Incorrect Answer
    C No change Correct Answer Incorrect Answer
    D The liquid evaporates Correct Answer Incorrect Answer

    Solution

    Ordinary evaporation is a surface phenomenon -since the vapor pressure is low and since the pressure inside the liquid is equal to atmospheric pressure plus the liquid pressure, bubbles of water vapor cannot form. But at the boiling point, the saturated vapor pressure is equal to atmospheric pressure, bubbles form, and the vaporization becomes a volume phenomena.

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