## Reversible/Irreversible Reactions

isochoric/isometric: $\Delta V = 0$
isothermal: $\Delta T = 0$
isobaric: $\Delta P = 0$

Megan Cao 1I
Posts: 103
Joined: Sat Sep 07, 2019 12:18 am

### Reversible/Irreversible Reactions

Can someone differentiate the characteristics of reversible and irreversible reactions? For example, I know that reversible reactions are done with infinitesimally changes. But I honestly can't think of anything else that distinguishes the two.

Sanjana Munagala_1j
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### Re: Reversible/Irreversible Reactions

Honestly that is the biggest difference, and because of the difference there are two different equations that can be used. For irreversible reactions, use the equation w=-P(change in V) since pressure would be constant. In a reversible reaction, use the integral equation which can be simplified to w=-nRTln(V2/V1) since pressure is not constant in this case.

Hope that helps!

Hussain Chharawalla 1G
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Joined: Sat Jul 20, 2019 12:15 am

### Re: Reversible/Irreversible Reactions

When you make infinetely small changes, your parameters such as pressure and volume are defined. When you make rapid changes, then they can no longer be defined. There is a khanacademy video that explains this topic well.

805307623
Posts: 99
Joined: Fri Aug 09, 2019 12:17 am

### Re: Reversible/Irreversible Reactions

In irreversible reactions, the reactants react to form products which can't form back into reactants. In reversible reactions, reactants react with other reactants to form products and products react with other products to form reactants at the same time.

Noe BM 1J
Posts: 50
Joined: Sat Sep 07, 2019 12:17 am

### Re: Reversible/Irreversible Reactions

Does anyone know if we need to know the integral equation for reversible reaction or just the simplified version?

Sanjana Munagala_1j wrote:Honestly that is the biggest difference, and because of the difference there are two different equations that can be used. For irreversible reactions, use the equation w=-P(change in V) since pressure would be constant. In a reversible reaction, use the integral equation which can be simplified to w=-nRTln(V2/V1) since pressure is not constant in this case.

Hope that helps!

Maya Pakulski 1D
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Joined: Thu Jul 11, 2019 12:17 am

### Re: Reversible/Irreversible Reactions

On a test question would it always specify that the reaction is happening irreversibly or reversibly?

Verity Lai 2K
Posts: 100
Joined: Sat Aug 24, 2019 12:18 am

### Re: Reversible/Irreversible Reactions

In one of the review sessions today, the TA gave a good example on how to differentiate. He said imagine two scales each with a pile of rocks on them. Irreversible expansion would be like removing all the rocks all at once and recording the difference of the scale in the instant. For reversible expansion, it's like removing each rock one at a time a recording the infinitesimal changes in the scale.