Four pounds of liquid lead at 750 F is poured into a form. It then cools at constant pressure down to room temperature at 68 F as heat is transferred to the room. The melting point of lead is 620 F, and the enthalpy change between the phases hif is 10.6 Btu/lbm. The specific heats are found in Table F.2 and F.3. Calculate the net entropy change for the lead.

