A metal of mass 0.5kg is heated to 100°C and then transferred to a well-lagged calorimeter of heat capacity 80JK-1 containing water of heat capacity 420JK-1 at 15°C. If the final steady temperature of the mixture is 25°C, find the specific heat capacity of the metal.
A. 877Jkg-1K-1 B. 286Jkg-1K-1 C. 133Jkg-1K-1 D. 92Jkg-1K-1
Correct Answer: C
Explanation
Let the specific heat cap. of the metal = C ∴ Heat lost by the metal = heat gained by the Calorimeter + Water ∴ 0.5 x C x [100 - 25] 80 x [25 - 15] + 420 [25 - 15] 0.5 x C x 75 = 80 x 10 + 420 x 10 37.5C = 800 + 4200 C = 5000/37.5 = 133.3Jkg-1K-1