In the continuous titration of a weak base (e.g., ) with a strong acid (e.g., ), which of the follow — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The equivalence point involves the WA-SB salt $NH_4Cl$, which undergoes cationic hydrolysis to yield an acidic solution ($pH < 7$). During titration, unreacted $NH_4OH$ coexists with formed $NH_4^+$, creating a classic basic buffer. Because the steep pH jump happens in the acidic region (pH 3 to 6), Methyl orange ($pH \approx 3.1 - 4.4$) is an excellent indicator. At half-equivalence, $[Base] = [Salt]$, so $pOH = pK_b$, meaning $pH = 14 - pK_b$, which is precisely the $pK_a$ of the conjugate acid. All statements are completely correct.