In an iron box weighing 300 grams, a student melted 100 g of tin.

In an iron box weighing 300 grams, a student melted 100 g of tin. What amount of heat was used to heat the box and melt the tin if their initial temperature was 32 degrees.

We find data on the properties of materials in the reference books:
– melting point of tin T₁ = 231.9 ° C;
– heat capacity of tin c₁ = 0.23 kJ / kg * K;
– latent heat of fusion of tin – 60700 J / kg;
– heat capacity of iron c₂ = 0.46 kJ / kg * K.
Both the tin and the capsule were heated from a temperature T₀ = 32 ° C to the melting point of tin T₁ = 231.9 ° C. In addition, some heat was expended in melting the tin from a solid to a liquid state.

Answer: 38.25 kJ.