A 500 g block of ice at -10°C is heated until it melts completely and the water
Practice Questions
Q1
A 500 g block of ice at -10°C is heated until it melts completely and the water is at 0°C. How much heat is required? (Specific heat of ice = 2.1 J/g°C, Latent heat of fusion = 334 J/g) (2000)
1050 J
1340 J
1500 J
2000 J
Questions & Step-by-Step Solutions
A 500 g block of ice at -10°C is heated until it melts completely and the water is at 0°C. How much heat is required? (Specific heat of ice = 2.1 J/g°C, Latent heat of fusion = 334 J/g) (2000)
Step 1: Identify the mass of the ice block, which is 500 grams.
Step 2: Determine the initial temperature of the ice, which is -10°C.
Step 3: Identify the final temperature after heating, which is 0°C.
Step 4: Calculate the temperature change needed to raise the ice from -10°C to 0°C. This is 0°C - (-10°C) = 10°C.
Step 5: Use the specific heat formula to calculate the heat required to raise the temperature of the ice: Heat = mass * specific heat * temperature change. Here, it is 500g * 2.1 J/g°C * 10°C.
Step 6: Calculate the heat required to raise the ice to 0°C: 500g * 2.1 J/g°C * 10°C = 10500 J.
Step 7: Identify the latent heat of fusion, which is 334 J/g. This is the heat required to melt the ice at 0°C.
Step 8: Calculate the heat required to melt the ice completely: Heat = mass * latent heat of fusion. Here, it is 500g * 334 J/g.
Step 9: Calculate the heat required to melt the ice: 500g * 334 J/g = 167000 J.
Step 10: Add the heat required to raise the temperature of the ice and the heat required to melt the ice: Total heat = 10500 J + 167000 J.
Step 11: Calculate the total heat required: 10500 J + 167000 J = 177500 J.
Specific Heat Capacity – The amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius.
Latent Heat of Fusion – The amount of heat required to convert a unit mass of a solid into a liquid without a change in temperature.
Heat Transfer Calculations – Calculating total heat required by summing the heat needed for temperature change and the heat needed for phase change.
