Final answer:
The heat required to melt 54 g of 0°C ice is calculated by the equation Q = mLf. Given a heat of fusion (Lf) of 80 cal/g for water, the total heat needed is 4320 calories.
Step-by-step explanation:
The student is asking about the amount of heat required to melt 54 g of ice at 0°C using the heat of fusion. The heat of fusion (Lf) is the amount of heat required to convert a solid at its melting point into a liquid without increasing the temperature. In this case, the heat of fusion for water is given as 80 cal/g.
To calculate the amount of heat required, you would use the equation Q = mLf, where:
- Q represents the total heat needed in calories
- m represents the mass of the substance to be melted in grams
- Lf represents the heat of fusion in cal/g
Substitute the given values into the equation:
Q = (54 g)(80 cal/g)
Q = 4320 cal
Therefore, 4320 calories of heat is needed to melt 54 g of ice at 0°C.