Hess Law  [ENDORSED]

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Chew 2H
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Hess Law

Postby Chew 2H » Thu Jan 11, 2018 1:43 pm

In Hess Law, if we flip the equation product reactant-wise, do we take the reciprocal of the enthalpy value or multiply it by '-'?

Farah Ahmad 2A
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Re: Hess Law

Postby Farah Ahmad 2A » Thu Jan 11, 2018 1:53 pm

You would just reverse the sign.

Janet Nguyen 2H
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Re: Hess Law

Postby Janet Nguyen 2H » Thu Jan 11, 2018 4:18 pm

yup basically multiply by (-)

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Re: Hess Law  [ENDORSED]

Postby Chem_Mod » Thu Jan 11, 2018 4:57 pm

Remember in class I discussed enthalpy is a state function. Therefore reversing the reaction must result in a change in sign for the enthalpy.

Alexandria Weinberger
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Re: Hess Law

Postby Alexandria Weinberger » Fri Jan 12, 2018 3:25 pm

You would just flip the sign, since the energy would be going (inflow or outflow) the opposite way.

Nehal Banik
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Re: Hess Law

Postby Nehal Banik » Fri Jan 12, 2018 6:18 pm

You would change the sign in that case because it is now the reverse of the reaction, therefore the enthalpy of the equation is now reversed you essentially multiply by -1

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