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A drug has pKa 5. at which PH it will be 99.9 percent ionized?
Wiki User
∙ 13y ago
For an acid: pH = pka + log ([ionised]/[unionised])
Therefore to get 99.9% ionised.
pH = 5 + log (99.9)
Therefore pH = 6.9996 (5s.f.)
Hope this helps.
Wiki User
∙ 13y ago
To determine at which pH a drug will be 99.9% ionized, we need to consider the Henderson-Hasselbalch equation. The pH at which a drug is 99.9% ionized can be estimated by finding the pH value that is one unit above the pKa of the drug. Therefore, in this case, the drug will be 99.9% ionized at a pH of 6.
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