Bond Angles

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Jasmin Argueta 1K
Posts: 69
Joined: Fri Sep 28, 2018 12:16 am

Bond Angles

Postby Jasmin Argueta 1K » Thu Jan 31, 2019 9:57 pm

Why is it that when bonds are formed we place a negative in front of the value? This is in regards to calculating enthalpy through bond angles in lecture.

Tuong-Minh Tran 1C
Posts: 30
Joined: Fri Sep 28, 2018 12:19 am

Re: Bond Angles

Postby Tuong-Minh Tran 1C » Thu Jan 31, 2019 10:05 pm

In enthalpy, the energy released by an exergonic reaction is represented by a negative value (since enegy in the system is lost), while the energy required to perform an endergonic reaction is represented by a positive value (because energy is added to the system). It happens to be that the formation of bonds is exergonic, so we place a negative in front of the value.

Meigan Wu 2E
Posts: 66
Joined: Fri Sep 28, 2018 12:29 am
Been upvoted: 1 time

Re: Bond Angles

Postby Meigan Wu 2E » Sat Feb 02, 2019 5:28 pm

Energy is required to break bonds (positive enthalpy change), while energy is released to form bonds (negative enthalpy change).

Porus_Karwa_2E
Posts: 72
Joined: Fri Sep 28, 2018 12:24 am

Re: Bond Angles

Postby Porus_Karwa_2E » Sat Feb 02, 2019 9:16 pm

The formation of bonds is exothermic, thus we place a negative sign.

Harshita Talkad 4L
Posts: 60
Joined: Fri Sep 28, 2018 12:16 am

Re: Bond Angles

Postby Harshita Talkad 4L » Sat Feb 02, 2019 10:00 pm

Forming bonds releases energy, so the negative sign represents the loss of energy from the system.

ran2000
Posts: 66
Joined: Fri Sep 28, 2018 12:15 am

Re: Bond Angles

Postby ran2000 » Sat Feb 02, 2019 10:40 pm

Bond formation is exothermic while bond breaking is exothermic. Hence, when bonds are formed, since they release energy, we put a negative sign before the values.


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