$\begin{aligned}
\mathrm{pH} & =\mathrm{pK}_a+\log \frac{[\text { salt }]}{[\text { acid }]} \
& =4.76+\log \frac{\frac{7.5}{500}}{\frac{5}{500}}=4.7+\log 1.5=4.87
\end{aligned}Hencecorrectansweris4.76 < \mathrm{pH} < 5.0$
What would be the pH of a solution obtained by mixing 5 g of acetic acid and 7.5 g of sodium acetate and making the volume equal to 500 mL ? (Ka=1.75×10−5,pKa=4.76)
Held on 25 Apr 2013 · Verified 6 Jul 2026.
pH=4.70
pH<4.70
pH of solution will be equal to pH of acetic acid
4.76<pH<5.0
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