Chem help (1 Viewer)

Frie

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When bonds are broken do they release energy..

Or is energy released when bonds are made...

Or does this depend on the nature of the reaction, either endothermic or exothermic.

I'm confused. >.<
 

bedpotato

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When bonds are broken, energy is absorbed. When bonds are made, energy is released.

Whether a reaction is endothermic or ectothermic depends on the amount of energy required to break bonds, and the amount of energy released when bonds are formed. Not the other way around.
 

AnimeX

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When bonds are broken do they release energy..

Or is energy released when bonds are made...

Or does this depend on the nature of the reaction, either endothermic or exothermic.

I'm confused. >.<
Think about it, so to break bonds you require energy to do so (so energy is absorbed). So when you form bonds get energy in return (energy released).
 

bedpotato

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Exoothermic:

N2 + 3H2 --> 2NH3

Energy is required to break the bonds between the N atoms in N2, and the H atoms in H2. Therefore, energy is absorbed. When the bonds in NH3 form, energy is released. For this reaction to be exothermic, heat has to be released overall. So, the amount of heat released when the bonds in NH3 form is greater than the amount of heat absorbed when the bonds in N2 and H2 are broken.

Endothermic:

The opposite is for endothermic reactions.

C + H2O --> CO + H2

Again, energy is required to break the bonds in H2O, and energy is released when the bonds in CO and H2 form. For this reaction to be endothermic, energy has to be absorbed overall. So, the amount of energy absorbed when the bonds in H2O are broken is higher than the amount of energy released when the bonds in CO and H2 form.

Hope this helps, and correct me if I might've said anything incorrect
 
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Frie

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Edit: Nvm, I think I got it now thanks to bedpotato.

Thank you very much.

Just realised this is like year 11 chem, it's kinda what an enthalpy graph explains, but my teacher didn't go into much detail because he said we would go over it in more depth this year, and then I got moved to a different class, :|
 
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bedpotato

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Edit: Nvm, I think I got it now thanks to bedpotato.

Thank you very much.

Just realised this is like year 11 chem, it's kinda what an enthalpy graph explains, but my teacher didn't go into much detail because he said we would go over it in more depth this year, and then I got moved to a different class, :|
Yes, it is exactly that.
 

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