Question about Problem 8.41

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Isa Samad 1L
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Question about Problem 8.41

Postby Isa Samad 1L » Sun Jan 14, 2018 9:40 pm

In the solutions manual, the answer uses the equation -q(water) = q(ice). Is this because the ice is lowering the temperature of the water?

Ashin_Jose_1H
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Re: Question about Problem 8.41

Postby Ashin_Jose_1H » Sun Jan 14, 2018 9:46 pm

Yeah. The heat from the water is transferred to the ice.

Erica Nagase 1H
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Re: Question about Problem 8.41

Postby Erica Nagase 1H » Thu Jan 18, 2018 10:27 am

The liquid water will lose heat and its temperature will decrease, and the ice will absorb that heat and melt/temperature will increase. This is why the q(water) is negative and q(ice) is positive.

Johann Park 2B
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Re: Question about Problem 8.41

Postby Johann Park 2B » Thu Jan 18, 2018 10:35 am

Yes, in thermodynamics we must remember that energy is conserved and that qsys + qsurr = 0, and thus qsys = -qsurr; the system being the ice and the surroundings being the water.

Meredith Steinberg 2E
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Re: Question about Problem 8.41

Postby Meredith Steinberg 2E » Thu Jan 18, 2018 12:00 pm

Yes because there is a transfer of heat from the water to the ice

Ashley Macabasco 2K
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Re: Question about Problem 8.41

Postby Ashley Macabasco 2K » Thu Jan 18, 2018 12:09 pm

In the solution manual -q(water)=q(ice) illustrates that heat from water is being transferred exothermically to the ice shown with the lose of heat (-q). The ice is then gaining heat endothermically from the water which can also be seen with q being positive for ice.


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