How much does the internal energy of a piece of lead weighing 0.3 kg, taken at the melting temperature

How much does the internal energy of a piece of lead weighing 0.3 kg, taken at the melting temperature, increase as a result of melting.

Problem data: m (mass of a piece of lead) = 0.3 kg.

Reference values: λ (specific heat of fusion of lead) = 0.25 * 10 ^ 5 J / kg.

The increase in the internal energy of a piece of lead is determined by the formula: Q = λ * m.

Calculation: Q = 0.25 * 10 ^ 5 * 0.3 = 7.5 * 10 ^ 3 J (7.5 kJ).

Answer: A piece of lead will increase its internal energy by 7.5 kJ.