
A 54.5g sample of polystyrene, which has a specific heat capacity of 1.880·J·g−1°C−1, is put into a calorimeter (see sketch at right) that contains 200.0g of water. The temperature of the water starts off at 21.0°C. When the temperature of the water stops changing it's 28.7°C. The pressure remains constant at 1atm.

Calculate the initial temperature of the polystyrene sample. Be sure your answer is rounded to 2 significant digits. Provide your reponse without using the word capacity.
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