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    Question

    How much mechanical work must be done to completely

    melt 1 gram of ice at 0°C?
    A 4 J Correct Answer Incorrect Answer
    B 80 J Correct Answer Incorrect Answer
    C 336 J Correct Answer Incorrect Answer
    D 2268 J Correct Answer Incorrect Answer

    Solution

    When water at 0 degree Celsius freezes, each gram of water gives off 80 calories. The temperature of the water stays at 0 degree C until every drop has frozen. When ice at 0 degree Celsius melts, it absorbs an equal amount of heat-80 calories for each gram of ice—and its temperature remains unchanged until it has completely melted.

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