Lead has a melting point of 327ºC, its specific heat is J/g•deg, and its molar enthalpy of fusion is 4.80 kJ/mol. How much heat, in kilojoules, will be required to heat a 500.0-g sample of lead from 23.0ºC to its melting point and then melt it?

Answer 1

q1 = heat to raise T from 23.0C to 327 C.
q1 = mass Pb x specific heat Pb x (Tfinal-Tinitial)

q2 = heat to melt Pb
q2 = mass Pb x heat fusion.

Total = q1 + q2
I note you have mass in grams in specific heat (not listed) in J/g*C so that's ok. However, when you go to the melting stage, you have mass in grams and heat fusion in kJ/mol. I would change heat fusion to J/g*C. When you finish adding q1 and q2 the answer will be in joules, convet that to kJ.

Answer 2

31760J=31.76KJ