Moderators: Chem_Mod, Chem_Admin

Bryce Ramirez 1J
Posts: 120
Joined: Sat Aug 24, 2019 12:16 am


Postby Bryce Ramirez 1J » Tue Feb 11, 2020 2:08 am

Can someone explain how to set up the calculations for solving the enthalpy using bond enthalpy. In part a of 4E.5 it has 3 C2H2 forms into C6H6, but I don't know how to find which bonds are actually used for calculating the net change.

Ashley Tran 2I
Posts: 108
Joined: Thu Jul 11, 2019 12:17 am

Re: 4E.5

Postby Ashley Tran 2I » Tue Feb 11, 2020 8:47 am

Drawing out the Lewis structures will indicate the types of bonds. Also it may be helpful to memorize some of the organic compounds. C6H6 is benzene and has ring shape with alternating single and double carbon carbon bonds.

Marni Kahn 1A
Posts: 107
Joined: Thu Jul 25, 2019 12:17 am
Been upvoted: 1 time

Re: 4E.5

Postby Marni Kahn 1A » Tue Feb 11, 2020 9:04 am

I typically draw out all of the compounds in the reaction and then observe which bonds must break in order to form those on the products side.

Posts: 118
Joined: Sat Aug 17, 2019 12:17 am

Re: 4E.5

Postby DHavo_1E » Tue Feb 11, 2020 1:42 pm


Could someone explain how they got the answer for the forming bonds for part a? Thank you!!

Sara Richmond 2K
Posts: 110
Joined: Fri Aug 30, 2019 12:16 am

Re: 4E.5

Postby Sara Richmond 2K » Tue Feb 11, 2020 4:15 pm

You first must draw out all of the Lewis structures. Then count all the bonds on the left side of the equation and all of the bonds on the right side of the equation. Then do bonds broken- bonds formed.

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