A steel ingot weighing 150 g, heated to 650 degrees, is dipped for quenching

A steel ingot weighing 150 g, heated to 650 degrees, is dipped for quenching in a vessel containing 800 g of water at 15 degrees. The water warmed up to 28 degrees. Find the specific heat of steel.

To calculate the specific heat capacity of steel, we use the equality: Cw * mw * (t – tн1) = Сс * mс * (tн2 – t), whence we express: Сс = Cw * mw * (t – tн1) / (mс * (tн2 – t)).

Constants and variables: Cw – specific heat capacity of water (Cv = 4200 J / (kg * K)); mw is the mass of water in the vessel (mw = 800 g = 0.8 kg); t – equilibrium temperature (t = 28 ºС); tн1 – initial water temperature (tн1 = 15 ºС); mс is the mass of a steel bar (mс = 150 g = 0.15 kg); tн2 – initial temperature of the ingot (tн2 = 650 ºС).

Calculation: Сс = Св * mв * (t – tн1) / (mс * (tн2 – t)) = 4200 * 0.8 * (28 – 15) / (0.15 * (650 – 28)) = 468, 17 J / (kg * K).