Thermodynamics Heat Calculation Problem

AI Thread Summary
To calculate the heat required to raise the temperature of a 500g copper kettle and 750g of water from 23°C to 100°C, the formula q=MCT is used. The heat for the water is calculated as 241,626 J, while the heat for the copper kettle is 16,093 J, totaling 257,719 J. The discrepancy with the book's answer of 260,000 J is attributed to significant figures, as the correct calculation aligns closely with the book's figure when rounded properly. The discussion emphasizes the importance of significant figures in thermodynamic calculations. Accurate calculations are essential for precise scientific communication.
wallace13
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Calculate the heat that must be supplied to a 500g copper kettle containig 750 g of water to raise its temperature from 23 degrees to the boiling point of water, 100 degrees.



q=MCT



qwater= 750 x 4.184 x 77= 241626 J

qcopper= 550 x .38 x 77= 16093 J

241626 + 16093 = 257719 J


The answer in the back of the book says 26000. So I'm not sure if its right and they rounded up or I did it wrong and just got lucky that my answer was close.
 
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Your answer is correct, but has the wrong number of significant figures. If you use the correct number of significant figures, your answer will also be 260 kJ (I assume you meant the book's answer was 260000 J, not 26000 J).
 
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