## breaking bond - heat released and gained

$PV=nRT$

905084274
Posts: 42
Joined: Fri Sep 28, 2018 12:22 am

### breaking bond - heat released and gained

I have a question related to both Biology and Chemistry. When I was at a PLF today for lifesci 7A, they said that when you break a bond, you go from high potential E to low potential E, which means that it is exergonic, because you release energy. However, I was told last quarter in chemistry that in order to break a bond it requires some energy. Therefore - I'm so confused which term is correct??

Karina Jiayu Xu 4E
Posts: 58
Joined: Fri Sep 28, 2018 12:29 am

### Re: breaking bond - heat released and gained

from what i learned in LS i think when u break a bond u release energy (so youre right). For example breaking off a phosphate from ATP will result in energy release.

Manu Vohra 1L
Posts: 61
Joined: Wed Oct 03, 2018 12:15 am

### Re: breaking bond - heat released and gained

When a bond is broken it does release energy, but in order to break that bond, usually some amount of energy is needed. The amount released by breaking the bond tends to be more than what is needed to initiate the breaking of that bond.

shaunajava2e
Posts: 66
Joined: Fri Sep 28, 2018 12:26 am

### Re: breaking bond - heat released and gained

Breaking Bonds Requires Energy. You have to put energy into a molecule to break its chemical bonds. The amount needed is called the bond energy.

Sapna Ramappa 1J
Posts: 63
Joined: Fri Sep 28, 2018 12:24 am

### Re: breaking bond - heat released and gained

In LS7A, we learned that the overall reaction would be exergonic, because it goes from a higher free energy to a lower free energy, thus resulting in a negative delta G. However, it is also true that breaking bonds requires energy.

jocelyntzeng
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: breaking bond - heat released and gained

it requires energy but it also releases energy so overall it is exothermic whereas making bonds just requires energy so it is endothermic