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An unknown metal of mass 192 g, heated to 100 degree C, is dropped into a brass calorimeter of mass 128 g containing 240 g of water at 8.4 degree C. The mixture settles at 21.5 degree C. Find the specific heat of the metal. (Specific heat of brass = 394 J/kg/K, specific heat of water = 4186 J/kg/K.)

1. 1232 J kg⁻¹ K⁻¹
2. 458 J kg⁻¹ K⁻¹
3. 654 J kg⁻¹ K⁻¹
4. 916 J kg⁻¹ K⁻¹

Correct answer: 916 J kg⁻¹ K⁻¹

Solution

Applying calorimetry, the metal's heat loss equals the heat absorbed by water and brass, which solves to about 916 J/kg/K.

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