The heat of fusion for gold at 1,063$^{\circ}$C is 66.6 kJ/kg and the specific heat of gold is 0.128 kJ/kg$^{\circ}$C.What is the energy needed to melt 100 grams of gold starting at 0$^{\circ}$C?

Question

Quizplus · Accepted Answer

The energy needed to melt the gold is the sum of the energy needed to raise the temperature of the gold from 0°C to 1063°C and the energy needed to melt the gold at 1063°C. The energy needed to raise the temperature of the gold is:Q1 = m * c * ΔT = (0.1 kg) * (0.128 kJ/kg °C) * (1063 °C - 0 °C) = 13.5 kJThe energy needed to melt the gold is:Q2 = m * Lf = (0.1 kg) * (66.6 kJ/kg) = 6.66 kJThe total energy needed is:Q = Q1 + Q2 = 13.5 kJ + 6.66 kJ = 20.16 kJ ≈ 20.3 kJTherefore, the correct answer is A.

The Heat of Fusion for Gold at 1,063 ∘^{\circ}∘ C Is 666 KJ/kg and the Specific Heat of Gold Is 0

The Heat of Fusion for Gold at 1,063 $^{\circ}$ C Is 666 KJ/kg and the Specific Heat of Gold Is 0