A 406.0 kg copper bar is put into a smelter for melting. The initial temperature of the copper is 300.0 K. How much heat must the smelter produce to completely melt the copper bar? (The specific heat for copper is 386 J/kg•K, the heat of fusion for copper is 205 kJ/kg, and its melting point is 1357 K.) A) 2.49 × 10⁵ kJ B) 1.66 × 10¹¹ kJ C) 1.66 × 10⁸ kJ D) 2.96 × 10⁵ kJ

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The correct answer is A.The heat required to melt the copper bar is the sum of the heat required to raise the temperature of the copper from 300.0 K to its melting point of 1357 K and the heat required to melt the copper at 1357 K.The heat required to raise the temperature of the copper is:Q1 = m * c * (T2 - T1)where:m is the mass of the copper bar (406.0 kg)c is the specific heat of copper (386 J/kg•K)T2 is the melting point of copper (1357 K)T1 is the initial temperature of the copper (300.0 K)Q1 = 406.0 kg * 386 J/kg•K * (1357 K - 300.0 K) = 1.66 × 10^8 JThe heat required to melt the copper is:Q2 = m * Lfwhere:Lf is the heat of fusion for copper (205 kJ/kg)Q2 = 406.0 kg * 205 kJ/kg = 8.32 × 10^7 JThe total heat required to melt the copper bar is:Q = Q1 + Q2 = 1.66 × 10^8 J + 8.32 × 10^7 J = 2.49 × 10^8 JTherefore, the smelter must produce 2.49 × 10^8 J of heat to completely melt the copper bar.

A 4060 Kg Copper Bar Is Put into a Smelter for for Melting