The quantity of heat Q that changes the temperature T of a mass m of a substance is given by Q = mcT, where c is the specific heat capacity of the substance. For example, for H20, c = 1 cal/g°C. And for a change of phase the quantity of heat Q that changes the phase of a mass m is Q = mL, where L is the heat of fusion or heat of vaporization of the substance. For example, for H20 the heat of fusion is 80 cal/g or 80 kcal/kg, and the heat of vaporization is 540 cal/g or 540 kcal/kg. Use these relationships to determine the number of calories to change
(a) 0.6 kg of 0°C ice to 0.6 kg 0°C ice water
kcal
(b) 0.6 kg of 0°C ice water to 0.6 kg 100°C boiling water
kcal
(c) 0.6 kg of 100°C boiling water to 0.6 kg l00°C steam
kcal
(d) 0.6 kg of 0°C ice to 0.6 kg 100°C steam
kcal

2. Originally Posted by johnjohn
The quantity of heat Q that changes the temperature T of a mass m of a substance is given by Q = mcT, where c is the specific heat capacity of the substance. For example, for H20, c = 1 cal/g°C. And for a change of phase the quantity of heat Q that changes the phase of a mass m is Q = mL, where L is the heat of fusion or heat of vaporization of the substance. For example, for H20 the heat of fusion is 80 cal/g or 80 kcal/kg, and the heat of vaporization is 540 cal/g or 540 kcal/kg. Use these relationships to determine the number of calories to change
(a) 0.6 kg of 0°C ice to 0.6 kg 0°C ice water
kcal
(b) 0.6 kg of 0°C ice water to 0.6 kg 100°C boiling water
kcal
(c) 0.6 kg of 100°C boiling water to 0.6 kg l00°C steam
kcal
(d) 0.6 kg of 0°C ice to 0.6 kg 100°C steam
kcal
Hello,

you only have to use all the given constants:

(a): $\displaystyle 600\ g \cdot 80\ \frac{cal}{g}=48000\ cal=48\ kcal$

(b): $\displaystyle 600 \ g \cdot 1 \ \frac{cal}{g \cdot ^\circ C} \cdot 100^\circ C=60000\ cal=60\ kcal$

(c): $\displaystyle 600\ g \cdot 540\ \frac{cal}{g}=324000\ cal=324\ kcal$