Hess's Law

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Akodjanian
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Joined: Mon Jan 26, 2015 2:17 pm

Hess's Law

Postby Akodjanian » Sat Jan 23, 2016 11:31 pm

What types of possible changes can be made to the given reactions (multiplication/division) in order to obtain the delta H for the net reaction?

Chem_Mod
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Re: Hess's Law

Postby Chem_Mod » Sun Jan 24, 2016 12:34 am

You can change the stoichiometry of a reaction by multiply the whole reaction by a number. You will have multiply the enthalpy of that reaction with the same number. You can add reactions/enthalpies to get the wanted net reaction.

Gabriel Esmailian 1F
Posts: 12
Joined: Tue Nov 25, 2014 3:00 am

Re: Hess's Law

Postby Gabriel Esmailian 1F » Sun Jan 24, 2016 2:40 pm

Multiplying/dividing in addition to flipping the direction of the reaction around when adding or subtracting. Just make sure that when you flip a reaction the delta H value associated with it takes on a negative sign.

Jana Sandhu 3J
Posts: 25
Joined: Fri Sep 25, 2015 3:00 am

Re: Hess's Law

Postby Jana Sandhu 3J » Sun Jan 24, 2016 4:24 pm

Remember when you multiply all the coefficients by a common number, that common number doesn't necessarily have to be or yield whole numbers. They could result in improper fractions as well.


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