## ICE Table Clarification

705192887
Posts: 77
Joined: Fri Sep 28, 2018 12:18 am

### ICE Table Clarification

When using an ICE table to determine equilibrium concentrations, when are we allowed to assume x is negligible for the reactant concentration so that we don't have to deal with the quadratic? Thanks

Julia Go 2L
Posts: 60
Joined: Sun Sep 30, 2018 12:17 am
Been upvoted: 1 time

### Re: ICE Table Clarification

We can approximate when the Ka or Kb value is less than 10^-3. A small Ka or Kb value means that the acid or base is very weak so not much is ionized during the reaction, which is why we can approximate when we solve for x.

Heesu_Kim_1F
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

### Re: ICE Table Clarification

I think the assumption was that x is negligible when k is equal to or less than 10^-3. To check, if x is less than 5% of initial concentration, then the approximation is valid. Hope this helps!

Raj_Bains_2C
Posts: 66
Joined: Fri Sep 28, 2018 12:25 am
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### Re: ICE Table Clarification

We are allowed to assume this when K is less than 10^-3.

Anmol_cheema_2F
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

### Re: ICE Table Clarification

When K is less than 10^-3, you can neglect x because it will probably be small enough to where it does not have any significant effect on the calculation.