Giving Qc or Qp when asked for Q

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Rachel Yoo 1F
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Joined: Fri Sep 28, 2018 12:24 am

Giving Qc or Qp when asked for Q

Postby Rachel Yoo 1F » Wed Jan 09, 2019 11:12 pm

For questions like 5G.11 when it asks you to write the reaction quotient Q for a certain equation, does it matter to answer with Qc or Qp?

Sam Joslyn 1G
Posts: 34
Joined: Fri Sep 28, 2018 12:20 am

Re: Giving Qc or Qp when asked for Q

Postby Sam Joslyn 1G » Thu Jan 10, 2019 9:10 am

It probably depends on the units that the question gives. If it gives the composition of the reaction in terms of pressure, use Qp, if it gives concentrations, use Qp

lindsey_ammann_4E
Posts: 61
Joined: Fri Sep 28, 2018 12:26 am

Re: Giving Qc or Qp when asked for Q

Postby lindsey_ammann_4E » Thu Jan 10, 2019 10:03 am

When they give you values in bars, use Qp. When they give you values in M (mol/L), use Qc.

Courtney Quan 1C
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Re: Giving Qc or Qp when asked for Q

Postby Courtney Quan 1C » Thu Jan 10, 2019 11:22 am

As mentioned above, whether you need to find Qc or Qp will usually be indicated by the units of the given quantities. Moles/liter specifies Qc whereas bars, atm, ex. indicates Qp. I've found that some of the questions will specifically ask for you to find Qp (rather than Qc) if needed.

Katelyn Phan 2A
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Joined: Fri Sep 28, 2018 12:23 am

Re: Giving Qc or Qp when asked for Q

Postby Katelyn Phan 2A » Thu Jan 10, 2019 1:45 pm

This depends on the given information. If you are given units of concentration then use Qc (if they give you the grams and liters this applies too) but if you're given units of pressure then use Qp!

mbaker4E
Posts: 69
Joined: Fri Sep 28, 2018 12:26 am

Re: Giving Qc or Qp when asked for Q

Postby mbaker4E » Thu Jan 10, 2019 3:20 pm

If the problem has to do with concentration (Mol/L) Qc will be used. If the problem has to do with pressure or gas-state molecules, Qp will be used.


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