## ICE Tables

Dustin Shin 2I
Posts: 64
Joined: Fri Sep 28, 2018 12:26 am

### ICE Tables

Can someone explain to me how ICE tables function in terms of concentration? Like how does one determine the initial concentrations? And how does one determine the change in terms of variables? Sorry if this is too long or confusing.

Jack DeLeon 1B
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

### Re: ICE Tables

Often when posed a question where an ICE table is necessary, you will be given initial concentrations for either the reactants or the products. And as for using variables for the change, a reaction in equilibrium allows you to assume the change (lets call it "x") in reactants is the same as the change in products, the only difference being that the reactant is decreasing in concentration (-x) and the product(s) are increasing on concentration(+x). These variables allow you to manipulate the formula for the equilibrium constant Kc to determine what the problem needs.

Dhwani Krishnan 1G
Posts: 63
Joined: Fri Sep 28, 2018 12:17 am

### Re: ICE Tables

For $A\rightleftharpoons B + C$

To make an ICE table, first enter all the numbers you are given into the table, and add in 0 in the "Initial" column if they're not given and there's no way to calculate it (you would be able to calculate it if you have Q, for example).
If you're given an equilibrium concentration of A, use that to calculate the change. The change for B and C would simply be -1*the change in A. Use the I and C values to calculate the E values.
If you're given K instead, use some variable 'X' for the change in A.

One thing to remember is if the equation has stoichiometric coefficients (eg. $A\rightleftharpoons 3B+4C$) then the change in B and C would be -3*(change in A) and -4*(change in A) respectively.