Infinite Forms of Hess's Law

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Mary Becerra 2D
Posts: 53
Joined: Fri Sep 29, 2017 7:06 am

Infinite Forms of Hess's Law

Postby Mary Becerra 2D » Sat Jan 13, 2018 8:23 pm

Are there infinite forms of Hess's Law? All the problems I have encountered usually have between 2-4 chemical reactions to use, but is it possible to have more than that in one problem? Or are we limited to the number of reactions?

Oscar Valdovinos 1I
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Joined: Fri Sep 29, 2017 7:05 am

Re: Infinite Forms of Hess's Law

Postby Oscar Valdovinos 1I » Sat Jan 13, 2018 8:26 pm

Technically we could use Hess law to connect hundreds of equations, but I don't think we are going to see that in our problems because it would pointless since 2-4 equations shows that we know the concepts associated with Hess's law.

Justin Chang 2K
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Joined: Fri Sep 29, 2017 7:04 am

Re: Infinite Forms of Hess's Law

Postby Justin Chang 2K » Sat Jan 13, 2018 10:30 pm

Yeah, you can use Hess’s Law indefinitely to calculate enthalpies, since enthalpy is a state function you can just keep on adding and adding enthalpies. However, I guess for time’s sake, 2-4 equations is enough to test our knowledge of how enthalpy works and how chemical reactions work (for example, if you need to multiply a reaction by 2, then the deltaH also needs to be multiplied by 2).

Aijun Zhang 1D
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Joined: Tue Oct 10, 2017 7:13 am

Re: Infinite Forms of Hess's Law

Postby Aijun Zhang 1D » Sun Jan 14, 2018 2:32 pm

I think most of the formulas given are between two to four in tests since the time to finish exam is needed to be counted into consideration. However, I believe you can write infinite forms for Hess's law, especially in organic chemistry.
Just consider the reactants and products and try to link them together with other reactions

Vincent Kim 2I
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Re: Infinite Forms of Hess's Law

Postby Vincent Kim 2I » Sun Jan 14, 2018 3:07 pm

There can be much more than 2-4 reactions involved with the use of Hess's Law, but it's not necessary to use all of them because it's possible to represent the steps of a chemical reaction with fewer steps.

Jessica Wakefield 1H
Posts: 58
Joined: Thu Jul 27, 2017 3:00 am

Re: Infinite Forms of Hess's Law

Postby Jessica Wakefield 1H » Sun Jan 14, 2018 9:36 pm

you could but for our purposes, i think we are only concerned with 2-4


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