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why does altering the ratio of weak acid : it's salt alter pH of the buffer solution? watch

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    So a weak acid and it's salt is used to make a buffer. If the ratio of them is changed the pH changes. My reasoning is that the amount of acid dissociation would be altered now. Am I right?
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    In a buffer the ratio is determined by Ka. Adding/removing H+ makes the ratio of [H+][A-]/[HA] no longer equal to Ka, so the equilibrium shifts until the ratio once again equals Ka.

    Which is a fancy way of saying, you are correct.
 
 
 
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