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Topic: another phase change problem  (Read 3700 times)

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Offline helpmeimnoob

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another phase change problem
« on: January 02, 2008, 08:58:47 PM »
ok, once again, i need help with another phase change problem:

what is the amount of energy that must be removed from 125.0 grams of water @ 35.7 degrees C when converted to ice @ 0.0 degrees C?

Ok, so I got this far:

4.18J/1g x deg C     X    125g    X 35.7 deg C = 18653.25

Then...

(something i dont know)/(something i dont know) x 125g = (something I dont know)

Can someone plugg the items in?


Offline Sev

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Re: another phase change problem
« Reply #1 on: January 02, 2008, 09:09:43 PM »
Lf of water is 334Jg-1.  So how much energy to convert 125g of water (at 00C) to ice?

Offline Alpha-Omega

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Re: another phase change problem
« Reply #2 on: January 02, 2008, 10:54:26 PM »
This is called Latent Heat:

•   Energy = mass X latent heat of fusion


You have everything you need Sev gave you the Latent Heat for water.

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