## Thursday Quiz 1, Question 3; See post for question

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

### Thursday Quiz 1, Question 3; See post for question

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

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
Posts: 5
Joined: Fri Sep 25, 2015 3:00 am

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

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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Joined: Fri Sep 25, 2015 3:00 am

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

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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