Specific Heat Capacity - Heat Absorbed - Physics - Thermodynamics
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# Specific Heat Capacity - Heat Absorbed - Physics - Thermodynamics

[From: ] [author: ] [Date: 12-12-20] [Hit: ]
What is the total amount of heat absorbed by the explorers sample of H20?A.B.C.D. 41.......
Hi there,

This question has been really bugging me for a while now. It is from a past exam paper and I am unsure why I cannot get the correct answer. The question is below:

An explorer takes 200 g of ice from an environment where the temperature is -40 degrees C, and places it in a kettle inside his mobile laboratory. The ice melts and he heats the water to +20 degrees C.
What is the total amount of heat absorbed by the explorer's sample of H20?

A. 543 kJ
B. 109 J
C. 100 kJ
D. 41.9 kJ
E. 83.5 J

Specific Heat Capacity of Ice: 2.09 Kj/Kg/C
Specific Heat Capacity of Water: 4.19 Kj/Kg/C

My attempt:
Change in temperature from -40 -> 0 = 40 degrees
40 degrees * 2.09 * .200 kg = 16.72 kJ

+

Change in temperature from 0 -> 20 degrees = 20 degrees
20 degrees * 4.19 * .200 kg = 16.76 kJ

For a total of 16.72 + 16.76 =33.48 kJ which is not one of the options.

Can anyone spot where I am going wrong please?

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your attempt is right, but you need to consider the latent heat of fusion,

for ice, it is around 334 kJ/kG

for 200g = 0.2*334 = 66.8