# How much heat must be communicated to melt a piece of lead weighing 0.5 kg

How much heat must be communicated to melt a piece of lead weighing 0.5 kg taken at a temperature of 27 degrees Celsius?

Initial data: m (mass of a given piece of lead) = 0.5 kg; tн (temperature at which the piece of lead was located) = 27 ºС.

Reference data: Cc (specific heat) = 140 J / (kg * ºС); tmelt (temperature of the beginning of the melting process) = 327.4 ºС; λ (specific heat of fusion) = 25 * 10 ^ 3 J / kg.

The amount of heat expended for heating and melting a piece of lead is determined by the formula: Q = Cc * m * (tmelt – t0) + λ * m.

Calculation: Q = 140 * 0.5 * (327.4 – 27) + 25 * 10 ^ 3 * 0.5 = 33 528 J.

One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.