The ionization constants of ortho-phthalic acid are \(K_{\mathrm{a}_{1}}=1.1
\times 10^{-3}\) and \(K_{\mathrm{a}_{2}}=3.9 \times 10^{-6}\) 1. \(\mathrm{C}_{6}
\mathrm{H}_{4}(\mathrm{COOH})_{2}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons
\mathrm{H}_{3} \mathrm{O}^{+}+\mathrm{HC}_{8} \mathrm{H}_{4}
\mathrm{O}_{4}^{-}\)
2\. \(\mathrm{HC}_{8} \mathrm{H}_{4} \mathrm{O}_{4}^{-}+\mathrm{H}_{2}
\mathrm{O} \rightleftharpoons \mathrm{H}_{3} \mathrm{O}^{+}+\mathrm{C}_{6}
\mathrm{H}_{4}\left(\mathrm{COO}^{-}\right)_{2}\) What are the pH values of the
following aqueous solutions: (a) 0.350 M potassium hydrogen orthophthalate;
(b) a solution containing 36.35 g potassium ortho-phthalate per liter? (f)
\(0.68 \mathrm{M} \mathrm{KCl}, 0.42 \mathrm{M} \mathrm{KNO}_{3}, 1.2
\mathrm{M} \mathrm{NaCl},\) and \(0.55 \mathrm{M}\)
\(\mathrm{NaCH}_{3} \mathrm{COO},\) with \(\mathrm{pH}=6.4\)