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Cold Pack Chemistry equations

Posted: Thu May 09, 2013 6:18 pm
by amyC
[Posted on behalf of student]
Project: Cold Pack Chemistry: Where Does the Heat Go? https://www.sciencebuddies.org/science- ... background

I'm trying to analyze my data and I'm having a difficult time with the equations. in equation 2, what do you fill in for grams of water and degrees celsius?
My data is as follows:
Cup 1- starting temperature-37 degrees celsius
1st reading-33
...

Re: Cold Pack Chemistry equations

Posted: Mon May 13, 2013 8:26 am
by kgudger
Hello and welcome to the forums

Equation 2 just shows you the heat capacity "in joules per gram per degrees Celsius, (J/g°C)". This number (4.18 J/g°C) is what you plug into equation 1 to get the energy. It would appear that your first reading is for 110 g of solution, with a 4 degree change in temperature (37-33). This means the energy absorbed by the ammonium nitrate is (4.18) * 110 * 4 = 461.47 J.

I hope this helps.
Keith