Thursday Quiz 1, Question 3; See post for question

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Timmy Gozali
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Thursday Quiz 1, Question 3; See post for question

Postby Timmy Gozali » Sat Feb 06, 2016 8:17 pm

I don't know if this is the right place to post, but regardless, it reads:

Steam is released from a geothermal vent at a temperature of around 180°C. Determine the amount of heat energy that must be removed from 1 kg of steam to be sold at a fancy restaurant as ice cubes, to a temperature of 0°C (Solid). (Useful information: specific heat of ice = 2.09 J/g°C, specific heat of water (l) = 4.18 J/g°C, specific heat of water (g) = 2.09 J/g°C, latent heat of fusion of water = 334 J/g, latent heat of vaporization of water 2257 J/g).

Guidance in how to do this problem would be helpful. Thanks in advance!

Chem_Mod
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Re: Thursday Quiz 1, Question 3; See post for question

Postby Chem_Mod » Sat Feb 06, 2016 8:41 pm

firstly i would draw out the heating curve, identify the phase change involved in the process. Then calculate q using q=-m*deltaH for phase change regions and q=m*C*(Tfinal-Tinitial) for non-phase change regions and add them together.

Timmy Gozali
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Joined: Fri Sep 25, 2015 3:00 am

Re: Thursday Quiz 1, Question 3; See post for question

Postby Timmy Gozali » Sat Feb 06, 2016 8:51 pm

So my answer would be negative, correct?

and is it negative because it is going from 180°C to 0°C?

Rachel Colbath 2G
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Re: Thursday Quiz 1, Question 3; See post for question

Postby Rachel Colbath 2G » Tue Feb 09, 2016 9:07 pm

Yes, your answer is negative because you are dealing with the heat removed from the gas, each step will be negative and they will all be added together.


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