HELP with INDUSTRIAL CHEMISTRY OPTION :) (1 Viewer)

[fatima96]

Can someone please explain the significance of 'Q' in relation to K?
If Q < K does that mean eqm shifts right? If so, why? And so forth for Q > K shifting left etc
Thanks

 

[faisalabdul16]

If Q<K, that means equilibrium lies to the left, meaning it favours the reverse reaction and will shift to right to establish an equilibrium.

 

[IR]

If Q<K, that means equilibrium lies to the left, meaning it favours the reverse reaction and will shift to right to establish an equilibrium.

Whats Q?

 

[dan964]

Q is the reaction quotient
K is the equilibrium constant which
is P/R
products over reactants.

So if Q<K, that means there are more reactants, so the equilibrium will favour the forward reaction (shift to the R) to bring it to equilibrium
So if Q>K, that means there are less reactants, so the equilibrium will favour the reverse reaction (shift to the L) to bring it to equilibrium
If Q = K then it is at equilibrium.

Note: temperature has to be constant.

 

[Cleverusername5321]

Pretty sure Q isn't in the syllabus. Our teacher told us that the author of Conq Chem HSC was whacked when he wrote that section lol.
The way we were taught was that

Where a, b, c, d are the number of moles and A, B, C, D are the substances.
Then you put those in into this equation:

And the answer you get will mean:

Solids and liquid (not gas) water have a concentration of 1.

To answer your question, Q is calculated the same way that K is calculated, and is used in comparison to K. Q shows the point where the reaction is currently at, whereas K shows the point at which the reaction is at equilibrium. If that makes any sense at all. I don't even know if that's right tbh, it's the way I understood it when I read Conq Chem HSC. I'll read it again and edit this post accordingly.

"A reaction is at equilibrium if its reaction quotient, Q, is equal to the equilibrium constant, K. If the reaction is not at equilibrium, Q has a value different from K, and a chemical reaction occurs until Q equals K, that is, until equilibrium is reached."

 

[fatima96]

Pretty sure Q isn't in the syllabus. Our teacher told us that the author of Conq Chem HSC was whacked when he wrote that section lol.
The way we were taught was that

Where a, b, c, d are the number of moles and A, B, C, D are the substances.
Then you put those in into this equation:

And the answer you get will mean:

Solids and liquid (not gas) water have a concentration of 1.

To answer your question, Q is calculated the same way that K is calculated, and is used in comparison to K. Q shows the point where the reaction is currently at, whereas K shows the point at which the reaction is at equilibrium. If that makes any sense at all. I don't even know if that's right tbh, it's the way I understood it when I read Conq Chem HSC. I'll read it again and edit this post accordingly.

"A reaction is at equilibrium if its reaction quotient, Q, is equal to the equilibrium constant, K. If the reaction is not at equilibrium, Q has a value different from K, and a chemical reaction occurs until Q equals K, that is, until equilibrium is reached."

I can actually remember coming accross a few qns in the trial papers that I have done which made mention of Q and asked us to tell whether eqm was shifting right and left. Just to be safe I've learnt it
Thank you for your answer BTW

 

[faisalabdul16]

Q is in the syllabus

 

[Cleverusername5321]

Q is in the syllabus

Yeah, I think you're right. I looked at past papers and they asked about Q in 2008.