Calculating Heat Absorbed When Melting 15g Lead

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The discussion focuses on calculating the heat absorbed when melting 15g of lead at its melting point. The formula used is Q = (LHf)(m), where LHf is the latent heat of fusion. One participant calculated the heat absorbed as 367.5J, while the provided answer was 306J, leading to confusion. Another participant confirmed the original calculation was correct using the latent heat value of 24.5 kJ/kg. The conclusion indicates that the worksheet publishers likely made an error in their answer.
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1. How much heat is absorbed when 15g of lead at its melting point are converted completely to a liquid at the same temperature?
2. (variables: Q=heat, LHf=latent heat of fusion, m=mass) Q=(LHf)(m)
3. I used the formula and I keep getting 367.5J. The answer I was given states that it is actually about 306J. I really don't understand...

Help would be gladly received
 
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Your answer is correct.
I get the same value using L=24.5 kJ/kg and m=0.015kg
 
I see...then the worksheet publishers must be in error. Thank you; I wasted a lot of time because I didn't want to get such a simple question wrong.
 

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