In an aluminum pan with a mass of 200 g, tin with a mass of 50 g was dissolved. How much heat was used to heat the pan and melt the tin if their initial temperature was 40 ° C?
Given: m1 (weight of the pan) = 200 g = 0.2 kg; m2 (mass of tin) = 50 g = 0.05 kg; t0 (initial temperature) = 40 ºС.
Constants: Ca (heat capacity of aluminum) = 920 J / (kg * K); Co (heat capacity of tin) = 230 J / (kg * K); λ (heat of fusion of tin) = 0.59 * 10 ^ 5 J / kg; tmelt (temperature of the beginning of melting) = 231.9 ºС.
Heat consumption: Q = Q1 + Q2 + Q3 = Ca * m1 * (tpl – t0) + Co * m2 * (tpl – t0) + λ * m2 = 920 * 0.2 * (231.9 – 40) + 230 * 0.05 * (231.9 – 40) + 0.59 * 10 ^ 5 * 0.05 = 40466.45 J ≈ 40.5 kJ.
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