## Negligible X

David Sarkissian 1K
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Joined: Fri Sep 28, 2018 12:21 am
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### Negligible X

What is the rule that can be applied when using an ice table that states you can ignore certain x values? I remember reading that it has to be less than 5% of the K value given, but always get confused when it comes to applying that rule. Something to do with 10^(-3)? Clarification would help out tremendously.

Diana Bibireata 1B
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

### Re: Negligible X

If the given K value is less than 10^-3 then you can use the approximation method where x is so small that the change it causes to the equilibrium concentration is negligible.

Carine Tamamian 2B
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

### Re: Negligible X

The 5% rule, so if your equilibrium value is smaller than 10^-3, you can ignore that x to make your calculation easier.

Mark 1D
Posts: 63
Joined: Fri Sep 28, 2018 12:18 am

### Re: Negligible X

X is zero if 5% of initial concentration or if K less than 10^-3