In: Physics
A foundry has an electric furnace that can melt 540 kg of copper. If the copper is initially at 20 ̊C, what amount of heat is needed to fully melt the metal if its melting point is 1080 ̊C? (Cp = .39 kJ/kg ̊C, Lf = 134 kJ/kg) Why doesn't the temperature of the copper change during the physical melting process?
Answers:
What amount of heat is needed to fully convert 200 g of ice at ‐25 ̊C to steam at 100 ̊C? (Cp,ice = 2.3 kJ/kg ̊C, Cp,water = 4.186 kJ/kg ̊C, Lf = 334 kJ/kg, Lv = 2,256 kJ/kg) What equation would you use to determine the heat required to raise the steam temperature past 100 ̊C?
Answers:
In order to find the amount of heat needed to melt the copper we have to use the formula for change in temperature and for Change in phase.
Q1=mC∆T
Q2=mL