Bond Enthalpy

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Arlene Paramo 1I
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

Bond Enthalpy

Postby Arlene Paramo 1I » Thu Jan 14, 2016 9:01 pm

When to do you make the standard reaction enthalpy negative? Is it when you're breaking or forming a bond and why does it need to be negative?

Matthew Gutierrez 2D
Posts: 19
Joined: Fri Sep 25, 2015 3:00 am

Re: Bond Enthalpy

Postby Matthew Gutierrez 2D » Thu Jan 14, 2016 9:06 pm

You make the bond enthalpy negative when you are forming a bond. It is negative because forming a bond is exothermic because the molecule becomes more stable and releases energy.

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

Re: Bond Enthalpy

Postby Gabriel Esmailian 1F » Sat Jan 16, 2016 6:23 pm

In order to break a bond, energy is needed. This uptake in energy constitutes a positive enthalpy value. On the other hand, to make bonds energy is release, and thus enthalpy value will be negative because energy is leaving the system.

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