Phase changes: A substance has a melting point of 20°C and a heat of fusion of 3.9 × J/kg. The boiling point is and the heat of vaporization is at a pressure of 1.0 atm. The specific heats for the solid, liquid, and gaseous phases are 600 J/(kg ∙ K), 1000 J/(kg∙K), and 400 J/(kg ∙ K), respectively. The quantity of heat required to raise the temperature of of the substance from to at a pressure of 1.0 atm, is closest to
A) 620 kJ.
B) 470 kJ.
C) 560 kJ.
D) 210 kJ.
E) 770 kJ.

Question

Phase changes: A substance has a melting point of 20°C and a heat of fusion of 3.9 ×  J/kg. The boiling point is  and the heat of vaporization is  at a pressure of 1.0 atm. The specific heats for the solid, liquid, and gaseous phases are 600 J/(kg ∙ K), 1000 J/(kg∙K), and 400 J/(kg ∙ K), respectively. The quantity of heat required to raise the temperature of  of the substance from  to  at a pressure of 1.0 atm, is closest to
A) 620 kJ. 
B) 470 kJ. 
C) 560 kJ. 
D) 210 kJ. 
E) 770 kJ.

Quizplus · Accepted Answer

The Answer of Phase changes: A substance has a melting point of 20°C and a heat of fusion of 3.9 ×  J/kg. The boiling point is  and the heat of vaporization is  at a pressure of 1.0 atm. The specific heats for the solid, liquid, and gaseous phases are 600 J/(kg ∙ K), 1000 J/(kg∙K), and 400 J/(kg ∙ K), respectively. The quantity of heat required to raise the temperature of  of the substance from  to  at a pressure of 1.0 atm, is closest to
A) 620 kJ. 
B) 470 kJ. 
C) 560 kJ. 
D) 210 kJ. 
E) 770 kJ.

Phase Changes: a Substance Has a Melting Point of 20°C