OMG this problem is making me mad

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The discussion addresses a physics problem involving the heat required to convert 2.50 kg of ice at -11.5°C to liquid water at 60.0°C. The user outlines their calculations, including the specific heat of ice and the heat of fusion for water, converting values to joules for accuracy. Initial calculations for heating ice, melting it, and then heating the water are presented. The user realizes a minor error in their conversion factor for specific heat, which leads to a correction in their final total heat calculation. The problem is ultimately resolved with the correct values, demonstrating the importance of precision in scientific calculations.
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OMG this problem is making me mad please help!

Homework Statement


How much heat is required to convert 2.50 kg of solid ice from a temperature of -11.5°C to liquid water at a temperature of 60.0 °C? (The specific heat of ice is cice = 0.50 kcal/kg°C and the heat of fusion for water is Lf = 79.7 kcal/kg.)

Homework Equations


The Attempt at a Solution


M = 2.5kg
Steps: -11.5 deg C to 0 deg C
Heat fusion at 0 deg C
0 deg C to 60 deg C

I converted bother specific heats to Jewels by multiplying by 1000 and 4.19
0.5 = 2095
79.7 - 333943

Q1 = M*Ci*CH T = 2.5 * 2095 * (0+11.5) = 60231.25J
Q2 = MLf = 2.5 * 333943 = 834857.5J
Q3 = M*Cw*CH T = 2.5 * 4190 * (60-0) = 10475J

Q1 + Q2 + Q3 = 9.06E^5 j
 
Last edited:
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nevermind I got it...I had to use 4186.8 instead of 4190!
 
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