ICE tables

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Marisa Gaitan 2D
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ICE tables

Postby Marisa Gaitan 2D » Thu Jan 07, 2021 3:16 pm

I know Lavelle hasn't gone over ICE tables in lecture yet, but I was wondering how we know when to use them and what the general procedure is. I'm a little rusty on my high school chem, and I vaguely remember using them, but need a quick refresher to help me with the homework.

darchen3G
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Re: ICE tables

Postby darchen3G » Thu Jan 07, 2021 3:35 pm

I is the initial concentration, C, is the change, and E is the equilibrium concentration.

For example, in A -> B + C, with initial concentration of A being 0.25M and C at equilibrium being 0.15
A B C
I 0.25 0 0
C -x +x +x
E 0.25-x x x
Then you know x = 0.15 and can use it to find K.

Felicia Wei 1B
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Re: ICE tables

Postby Felicia Wei 1B » Thu Jan 07, 2021 3:39 pm

darchen3G wrote:I is the initial concentration, C, is the change, and E is the equilibrium concentration.

For example, in A -> B + C, with initial concentration of A being 0.25M and C at equilibrium being 0.15
A B C
I 0.25 0 0
C -x +x +x
E 0.25-x x x
Then you know x = 0.15 and can use it to find K.


I just wanted to add on that to find K you use the values in the E row so K=x^2/(0.25-x)

HannahRobinson3L
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Re: ICE tables

Postby HannahRobinson3L » Thu Jan 07, 2021 3:44 pm

You can also go watch the Audio Visual Focus Topics on Dr. Lavelle's website if you want to hear an explanation directly from the professor! I think it is the Chemical Equilibrium Part 2 where he goes over ICE charts.

Marco Morales 2G
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Re: ICE tables

Postby Marco Morales 2G » Thu Jan 07, 2021 5:34 pm

HannahRobinson3L wrote:You can also go watch the Audio Visual Focus Topics on Dr. Lavelle's website if you want to hear an explanation directly from the professor! I think it is the Chemical Equilibrium Part 2 where he goes over ICE charts.

I recommend doing what Hannah said. In the module, he goes over it super well!

Nayra Gharpetian 3F
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Re: ICE tables

Postby Nayra Gharpetian 3F » Thu Jan 07, 2021 5:37 pm

I is initial concentrations, C is change in concentrations, and E is concentrations at equilibrium. Depending on what information we're given, we can use ICE tables to find the K value, or concentrations at equilibrium (if we already know the K value).

Sabrina Galvan 3J
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Re: ICE tables

Postby Sabrina Galvan 3J » Thu Jan 07, 2021 6:27 pm

To answer the first part of your question, we would use them if we're given the initial concentrations and the Kc/p of a reaction, and we are asked to find the the concentrations at equilibrium.

Sabrina Galvan 3J
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Re: ICE tables

Postby Sabrina Galvan 3J » Thu Jan 07, 2021 6:30 pm

darchen3G wrote:I is the initial concentration, C, is the change, and E is the equilibrium concentration.

For example, in A -> B + C, with initial concentration of A being 0.25M and C at equilibrium being 0.15
A B C
I 0.25 0 0
C -x +x +x
E 0.25-x x x
Then you know x = 0.15 and can use it to find K.


Just to add onto this, because only the concentration of A is given, we know that both B and C have to have a concentration of zero because the reaction has not progressed long enough for the productions to form. Additionally, when calculating the X, you will be given two x values. You disregard the x values that are negative because it is not possible to have a negative concentration, and you disregard values that are above the initial concentrations given on the basis of the law of the conservation of mass.

Andrew Yoon 3L
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Re: ICE tables

Postby Andrew Yoon 3L » Thu Jan 07, 2021 10:31 pm

Just to ask, if we are given a value for the products in the question as well has initial values for the reactants, would we include them in the I part of the ICE table?

Mackenzie Stockton 2H
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Re: ICE tables

Postby Mackenzie Stockton 2H » Fri Jan 08, 2021 10:56 am

I= initial concentration. This is the concentration of each reactant and product (mol/L) that you start off with
C= change in concentration. The reactant usually will have a decrease in concentration that is proportional to the increase in concentration in the product. If there is one mol of a reactant for every 2 mol of product, when the product increases by a certain concentration X, the reactant will decrease in concentration by 0.5X because of the molar ratio.
E= equilibrium concentration. Generally one of the equilibrium concentrations will be given, and you apply the change in concentration for this given value for a certain species to the other reactants and products.

ICE tables allow you to find the equilibrium concentrations of reactants and products, and therefore Kc.

ellenulitsky Dis 1I
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Re: ICE tables

Postby ellenulitsky Dis 1I » Fri Jan 08, 2021 11:54 am

Is an ICE table to only way to solve questions when missing one of the concentration values?

Jayasree Peri 2J
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Re: ICE tables

Postby Jayasree Peri 2J » Fri Jan 08, 2021 11:55 am

ellenulitsky Dis 1I wrote:Is an ICE table to only way to solve questions when missing one of the concentration values?

The only time you don't need an ICE table is if you have all your necessary equilibrium concentrations. Otherwise, an ICE table is the easiest way to find your equilibrium concentrations.


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