Endothermic vs Exothermic Stabilities

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Sid Panda 3A
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Endothermic vs Exothermic Stabilities

Postby Sid Panda 3A » Wed Jan 06, 2021 8:08 am

Would the products of endothermic reactions generally be less stable than the products of a exothermic reaction?

My reasoning is that we are adding heat in an endothermic reaction, which would be "forcing" a reactant to turn into a products by breaking the bonds of the reactant. If you need to forcibly break the bonds of a reactant by adding heat to make it a product, then wouldn't the product be more unstable? On the other hand, when an exothermic reaction is releasing heat once it makes its products, then it is "relieving" some of the tension of the bonds in the reactants (for the lack of better terms), so it would be favorable to make more product.

Stuti Pradhan 2J
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Re: Endothermic vs Exothermic Stabilities

Postby Stuti Pradhan 2J » Wed Jan 06, 2021 11:11 am

I believe you are correct. The way I think of it is that anything with lower energy is more stable, so in an endothermic reaction the products would have more energy than the reactants and therefore, be less stable. On the other hand, in an exothermic reaction, the products would have a lower energy than the reactants since energy is released, making it more stable.

Hope this helps!

Saja Kamal 2L
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Re: Endothermic vs Exothermic Stabilities

Postby Saja Kamal 2L » Wed Jan 06, 2021 11:14 am

Hi Sid!

In an exothermic reaction, the change in enthalpy is always negative and energy is being released. When looking at an energy diagram for an exothermic reaction, you will see that the reactants are at a higher energy level while the products are at a visibly lower energy level. The reasoning for such is due to energy being released since the total energy is P<R, hence it is in lower energy. And thus, an exothermic reaction has products with more stable bonds/more favorable. Lower energy = greater stability.

While, endothermic reactions will have products with higher energy, and in turn they are less stable. The change in enthalpy is always positive and energy is being absorbed. When looking at an energy diagram for an endothermic reaction, you will see that the reactants are at a lower energy level while the products are at a visibly higher energy level.

I hope this helps!

Sameer Chowdhury 3C
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Re: Endothermic vs Exothermic Stabilities

Postby Sameer Chowdhury 3C » Sun Jan 10, 2021 1:37 pm

I think you would be right mainly because stability has to do with energy, molecules and compounds that are of lower energy are more stable than those with higher energy.

Inderpal Singh 2L
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Re: Endothermic vs Exothermic Stabilities

Postby Inderpal Singh 2L » Wed Jan 20, 2021 1:14 pm

I think your reasoning is accurate. Compounds with less energy are considered more stable than those with higher energy, and exothermic reactions release energy.

Emma_Barrall_3J
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Re: Endothermic vs Exothermic Stabilities

Postby Emma_Barrall_3J » Thu Jan 21, 2021 12:18 pm

I think you're right! You can also look at the curves of endothermic and exothermic reactions but I don't think we've learned that

Xavier Herrera 3H
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Re: Endothermic vs Exothermic Stabilities

Postby Xavier Herrera 3H » Thu Jan 21, 2021 3:44 pm

You're right because lower energy is favored in reactions. So in an endothermic reaction, the products are less stable than the reactants because the products have more energy than the reactants. So the reaction would naturally want to go in the reverse direction, towards less energy. On the other hand, the products of an exothermic reaction have less energy than the reactants, so the forward reaction is favored due to the products having the least energy.

Jonathan Haimowitz 3B
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Re: Endothermic vs Exothermic Stabilities

Postby Jonathan Haimowitz 3B » Thu Jan 21, 2021 8:10 pm

It is true that the products of an exothermic reaction tend to be more stable than the reactants of that reaction, and the products of an endothermic reaction tend to be less stable than the reactants of that reaction.
However, this relationship only tells you about the reactants and products in the same reaction.
If you have two completely separate reactions, one exothermic and one endothermic, you cannot tell which reaction has more stable products compared to the other reaction's products from this information alone, only which is more stable relative to the same reaction's reactants.

austin-3b
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Re: Endothermic vs Exothermic Stabilities

Postby austin-3b » Fri Jan 22, 2021 12:53 pm

You are correct. Exothermic reactions where things that go to a lower energy state are generally more stable. Endothermic is vice versa. If elements go to a higher energy state, they are generally less stable.


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