∆H equation

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Maria Bajenov 1I
Posts: 28
Joined: Fri Sep 29, 2017 7:06 am

∆H equation

Postby Maria Bajenov 1I » Sat Jan 20, 2018 11:59 am

For calculating ∆H, you solve for KJ(energy)/mol. The mol corresponds to n, but what constant corresponds to KJ?

905022356
Posts: 48
Joined: Mon Oct 02, 2017 7:19 am

Re: ∆H equation

Postby 905022356 » Sat Jan 20, 2018 12:52 pm

If you are referring to the equation q= nCmΔT, the molar heat capacity of the substance will tell you how many joules are necessary to increase the temperature of one mol of the substance by 1 degree Celsius or Kelvin. By substituting each value into this equation, you will get a ΔH in joules per mol. To convert it to kJ per mol, you just have to divide that value by a thousand.

Angel Gomez 1K
Posts: 36
Joined: Fri Sep 29, 2017 7:04 am

Re: ∆H equation

Postby Angel Gomez 1K » Sat Jan 20, 2018 2:00 pm

Isn't the equation for finding change in heat as follows:
I know that the m accounts for mass instead of moles(which is usually represented as n), so would we simply switch out the m for n if we are presented with molar heat capacity?

905022356
Posts: 48
Joined: Mon Oct 02, 2017 7:19 am

Re: ∆H equation

Postby 905022356 » Sun Jan 21, 2018 5:26 pm

There are two different equations. The first one, ΔH = mCΔT is found using the specific heat capacity of the substance, and m stands for the mass of the substance in grams. The second one, ΔH = nCΔT is found using the molar heat capacity of the substance, and n stands for the number of mol of the substance.


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