Answer to Question #190169 in General Chemistry for Emaan

Question

Determine the quantity of energy that will be needed to melt 2.5 X 105 Kg of iron at its melting 

point 1536°C. The enthalpy of fusion of iron is 13.807 kJ/mol.

Answer 1

2.5 X 10$^{5}$ kg = 2.5 X 10$^{8}$ g of Fe.

number of moles of Fe= mass of Fe$/$ Atomic weight of Fe= 2.5X10$^{8}/$ 55.85 = 44.76 X 10$^{5}$ moles of Fe.

Ethalpy of fusion=13.807 kJmol$^{-1}$

Thus, 1mole requires 13.807kJ energy. Therefore 44.76 X 10$^{5}$ moles requires 44.76 X 10$^{5}$ X 13.807 kJ = 618 X 10$^{5}$ kJ energy.