8.41

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Shannon Wasley 2J
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8.41

Postby Shannon Wasley 2J » Fri Jan 26, 2018 10:41 am

Why when calculating the heat of the ice cube do we use the specific heat capacity of water (4.184)? Why wouldn't we use the specific heat capacity of ice (2.108)?

Hubert Tang-1H
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Re: 8.41

Postby Hubert Tang-1H » Fri Jan 26, 2018 12:00 pm

It is because the ice melts at 0.0 C in the problem, and becomes water. We therefore use the specific heat of water rather than ice.

Emma Miltenberger 2I
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Re: 8.41

Postby Emma Miltenberger 2I » Fri Jan 26, 2018 1:04 pm

In this problem, the ice melts and turns into water. Therefore, you use the specific heat capacity of water.

Angel Ni 2K
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Re: 8.41

Postby Angel Ni 2K » Fri Jan 26, 2018 4:41 pm

Use the specific heat capacity of ice when you are raising the temperature of ice. Because the ice is already at 0C, you don't need to use the specific heat capacity of ice because the ice doesn't get warmer than 0C. Instead, use the heat of fusion to calculate the energy needed to melt the ice, then use specific heat of liquid water to calculate the energy needed to raise the temperature.

Sara Varadharajulu
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Re: 8.41

Postby Sara Varadharajulu » Fri Jan 26, 2018 11:13 pm

for these types of problems, I would highly encourage drawing a diagram---this helps you keep track of the state of the substance at hand so you now the correspond specific heat capacity. since ice melts into water before the water raises temperature, you need to use the specific heat capacity of water.

DamianW
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Re: 8.41

Postby DamianW » Sun Jan 28, 2018 6:27 pm

In this problem do you have to account for fusion as well ?

Emma Li 2C
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Re: 8.41

Postby Emma Li 2C » Sun Jan 28, 2018 6:38 pm

DamianW wrote:In this problem do you have to account for fusion as well ?


Yes! Since there is a difference in temperature between the ice cube and the water, the ice cube would first melt (enthapy of fusion) and then have a temperature change.


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