How to assume X is too small
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How to assume X is too small
Is there any way to assume X to be too small without calculating the actual value of X and using the 5% rule?
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Re: How to assume X is too small
I don't think so. My TA went over this today in discussion and said that when doing concentration calculations you're almost always going to assume X is too small and then check with the 5% rule. However, he did mention that if the concentration given is rather large (in the example in class it was 0.510 M CH3NH3+) then it is very unlikely that the X value will be large enough to make a difference.
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Re: How to assume X is too small
I think Dr. Lavelle mentioned that if K is less than 10^-4, then it can generally be assumed that X will be small enough to ignore, but we should definitely still check to make sure at the end.
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Re: How to assume X is too small
Normally in a reaction with extremely small K, we can apply the 5% rule, but make sure that the answer is less than 5% of the original concentration
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