Calculating Heat Absorbed When Melting 15g Lead

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The calculation of heat absorbed when melting 15g of lead at its melting point involves using the formula Q = (LHf)(m), where LHf is the latent heat of fusion. The correct value for the latent heat of fusion for lead is 24.5 kJ/kg. When applying this value, the heat absorbed is calculated as Q = 24.5 kJ/kg * 0.015 kg, resulting in 367.5 J. The discrepancy with the worksheet's answer of 306 J indicates an error on their part.

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Mathys
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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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