## Giving Qc or Qp when asked for Q

Rachel Yoo 1F
Posts: 65
Joined: Fri Sep 28, 2018 12:24 am

### Giving Qc or Qp when asked for Q

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

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

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

Courtney Quan 1C
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am
Been upvoted: 2 times

### Re: Giving Qc or Qp when asked for Q

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
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

### Re: Giving Qc or Qp when asked for Q

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

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.