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I read this somewhere but now that I think about it this can't be correct, can it?
Ka for strong acids is irrelevant but yes that seems too low for strong acids as 1 means half-dissociating in water
Why Ka is irrelevant? I thought that the strong acid by definition is the acid that disassosiates completely. (is that correct?) Well, nothing is complete, and that means that Ka is just a very very big number, like 10^60 , it may not be measurable since [HA] concentration is very small. Ka=1 does not look like a big number to me
Hmm...isn't the equation Ka =[H+][A-]/[HA]? And at equilibrium (for example initial [HA] = 1M), [H+] = [A-] = x, while [HA] = 1 - x? So, 1 = (x^2)/(1-x). If half of it has dissociated, wouldn't the value of x be 0.5, so (0.5*0.5)/(0.5) equals 0.5, not 1?no a Ka of 1 would be exactly half - hardly acceptable under the casual "strong acid" definition
given a fixed Ka, the ratio of [a] to [ha] shifts depending on originial [ha]. which makes sense. i.e. an acid that might dissociate exactly halfway at a certain concentration will not at another.l