Pka=pH when[HA]=[A- ]. What is [A-]/[HA] WHEN PH=PKA+1 AND WHEN pH=pka-1

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  1. pH = pKa + log (A^-)/(HA)
    When (A^-)/(HA) = 1, log 1 = 0 and pH = pKa.

    When pH = pKa + 1, (A^-)/(HA) = 10 BECAUSE log 10 = 1.

    I'll leave the pKa-1 for you to do.

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  2. When pH = pKa - 1, (A^-)/(HA) = 0.1 BECAUSE log 0.1 = -1.

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