3 Different Methods

Moderators: Chem_Mod, Chem_Admin

104922499 1F
Posts: 53
Joined: Fri Sep 29, 2017 7:04 am

3 Different Methods

Postby 104922499 1F » Sun Jan 14, 2018 7:59 pm

During lecture, Lavelle went over the different methods to solve enthalpy. How do you know when to use each method?

Grace Ramey 2K
Posts: 57
Joined: Thu Jul 27, 2017 3:01 am

Re: 3 Different Methods

Postby Grace Ramey 2K » Sun Jan 14, 2018 8:03 pm

It is determined by what information is given to you in the problem. For example, if you were given a chemical equation along with a list of bond enthalpies for the different bonds involved in that chemical reaction, you would use the bond enthalpy method. If you were given a number of chemical equations and the delta H for each chemical equation, you would most likely use the method where you manipulate, add, and subtract the equations to derive the equation you want and the corresponding enthalpy of that reaction.

Rachel Formaker 1E
Posts: 86
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 2 times

Re: 3 Different Methods

Postby Rachel Formaker 1E » Sun Jan 14, 2018 8:15 pm

Adding onto the previous response, if you are given the standard enthalpies of formation for the reactants and products, you use the equation:
Σ ΔHorxn = Σ ΔHof(products) - Σ ΔHof(reactants)

Return to “Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)”

Who is online

Users browsing this forum: No registered users and 1 guest