Question

apply the first law of thermodynamics to determine the change in internal energy during boiling and melting process​

Answer 1

Therefore, dW= P (dV) = P x 0 = 0. So, the internal energy during the melting process increases by (mL) at constant temperature. This is due to increase in internal potential energy (UP). The internal kinetic energy ( UK ) remains constant.

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Adiabatic Process.

dQ = dU + dW = 0

or dU = – dW

Answer 2

Answer:

Therefore, dW= P (dV) = P x 0 = 0. So, the internal energy during the melting process increases by (mL) at constant temperature. This is due to increase in internal potential energy (UP). The internal kinetic energy ( UK ) remains constant.