ICE Tables

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LeAirraBullingor2k
Posts: 77
Joined: Wed Mar 13, 2019 12:15 am

ICE Tables

I need some help figuring out how to complete ice tables. How do we know to use -X or X?

Althea Zhao 1B
Posts: 101
Joined: Mon Jun 17, 2019 7:24 am

Re: ICE Tables

Since the reaction begins with only reactants and moves towards equilibrium as products form, the amount of reactant decreases and the amount of product increases. So, you use +x for products and -x for reactants

Alfred Barrion 2H
Posts: 100
Joined: Sat Jul 20, 2019 12:16 am

Re: ICE Tables

you use -x typically for the reactants and +x for the products

JohnWalkiewicz2J
Posts: 103
Joined: Thu Jul 11, 2019 12:17 am
Been upvoted: 1 time

Re: ICE Tables

One way that you can help figure out if the reaction is proceeding forwards (-x from reactants) or backwards (-x from products) is to look at the the Keq (equilibrium constant) if it provides it in the question. If the Keq is < (1.0 x 10^3), then the reaction will proceed forward(-x from reactants, +x to products). If the Keq is larger than (1.0 x 10^3), then the reaction will proceed backwards(+x to reactants, -x from products).

Jesse Anderson-Ramirez 3I
Posts: 54
Joined: Thu Sep 26, 2019 12:18 am

Re: ICE Tables

It depends on whether the reaction is going forward or reverse. This is found by comparing the reaction quotient (Q) and the chemical equilibrium (K).

005162520
Posts: 101
Joined: Tue Sep 24, 2019 12:17 am

Re: ICE Tables

Usually +x is used for products and -x is used for reactants, but it does depend if it is a forward or reverse reaction.

MTanikella_1K
Posts: 110
Joined: Sat Jul 20, 2019 12:16 am

Re: ICE Tables

This depends on each reaction, but if the reaction is moving in the forward direction, reactants in the ice table will have a change of -x and products in the ice table will have a change of +x.

Leonardo Le Merle 1D
Posts: 56
Joined: Wed Feb 27, 2019 12:16 am

Re: ICE Tables

+ X is generally used for products and - X for reactants, as the former is produced from reaction and the latter is used up. However, I'm sure it depends on the context of the question.

Ying Yan 1F
Posts: 101
Joined: Fri Aug 02, 2019 12:16 am

Re: ICE Tables

If you are only given intial concentrations of the reactant and products and the K value, then create an equilibrium ratio and solve for Q. If Q < K, then the reaction is moving in the forwrd direction, and the reactants will have -x while the product is +x. On the other hand, if Q > K, then the reaction is moving in the reverse direction and the reactants will be -x and products will be +x. *Note: MOST of the time, the reactants will be -x and the products will be +x. Hope that helps!