What not to count

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Ethan Breaux 2F
Posts: 63
Joined: Sat Sep 29, 2018 12:16 am

What not to count

Postby Ethan Breaux 2F » Fri Jan 25, 2019 3:22 pm

I know that when doing the ICE box you don't count Cl, Na, or H2O but are there any other elements that we just inherently disregard?

Ray Guo 4C
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Joined: Fri Sep 28, 2018 12:15 am

Re: What not to count

Postby Ray Guo 4C » Fri Jan 25, 2019 3:34 pm

Do you mean what not to include in equilibrium constant formula? If so then you should just disregard anything in solid and liquid state.

anthony_trieu2L
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

Re: What not to count

Postby anthony_trieu2L » Fri Jan 25, 2019 3:44 pm

If you are talking about salt solutions, then you must disregard ions that fully dissociate because they do not affect the pH of the solution. For example, cations of strong bases do not affect pH because they fully dissociate. The same applies to anions of strong acids.

Carissa Young 1K
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Joined: Fri Sep 28, 2018 12:17 am

Re: What not to count

Postby Carissa Young 1K » Fri Jan 25, 2019 6:17 pm

As stated before, don't use solid or pure liquid concentrations in the equilibrium constant equation. For water, you would only put it in the equation if it is in the gas phase.

705170809
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Re: What not to count

Postby 705170809 » Sun Jan 27, 2019 3:20 pm

You should only include gases in ICE tables, so any liquids or solids should be omitted. However, be careful because sometimes H20 can be a vapor, and thus a gas, so if it is in gas form, it should be included in your ICE table.

eden tefera 2B
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Joined: Fri Sep 28, 2018 12:21 am

Re: What not to count

Postby eden tefera 2B » Sun Jan 27, 2019 3:50 pm

You can typically disregard elements that don't affect the pH/pOH.

Timothy_Yueh_4L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

Re: What not to count

Postby Timothy_Yueh_4L » Sun Jan 27, 2019 8:19 pm

In general you disregard any ions from the 1st group, 2nd group, and the halogens which act as spectator ions. Others such as compounds in the form of solids and liquids are also ignored.

allisoncarr1i
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Joined: Fri Sep 28, 2018 12:15 am

Re: What not to count

Postby allisoncarr1i » Sun Jan 27, 2019 9:51 pm

Any element that is in its liquid or solid form can be disregarded.

Diana Sandoval 1K
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Re: What not to count

Postby Diana Sandoval 1K » Sun Jan 27, 2019 10:15 pm

This would be anything that is in the liquid or solid state, everything else is counted. Same goes when looking for K.

Karina Jiayu Xu 4E
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Joined: Fri Sep 28, 2018 12:29 am

Re: What not to count

Postby Karina Jiayu Xu 4E » Sun Feb 03, 2019 3:29 pm

You should just ignore everything thats not in a gaseous state


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