The Henderson equation for the given acidic buffer can be written as
pH=pKa+log[weakacid][salt]
5=pKa+log25×0.0225×0.2⇒pKa=4⇒Ka=10−4=10×10−5
Hence, the value of xis 10.
JEE Main 2023 — Chemistry Physical Chemistry
The dissociation constant of acetic is x×10–5. When 25mLof0.2MCH3COONa solution is mixed with 25mLof0.02MCH3COOH solution, the pH of the resultant solution is found to be equal to 5. The value of x is _______.
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