Chapter 45

Show that the pH reading in the model is correct (given that the hydronium ion concentration is \(5.0 \times 10^{-4} \mathrm{M}\) ).

Consider a neutral aqueous solution: a) What is the \(\mathrm{pH}\) of a neutral aqueous solution? b) What is the pOH of a neutral aqueous solution?

What values of pH characterize: a) an acidic solution? b) a basic solution?

Recall that \(\log (\mathrm{A} \times \mathrm{B})=\log \mathrm{A}+\log \mathrm{B}\). What is the relationship between \(\mathrm{pH}\), \(\mathrm{pOH}\), and \(\mathrm{p} K_{\mathrm{w} ?}\)

For a weak acid, \(\mathrm{HA}\) : $$ \mathrm{HA}(\mathrm{aq})+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{H}_{3} \mathrm{O}^{+}(\mathrm{aq})+\mathrm{A}^{-}(\mathrm{aq}) $$ a) Write the equilibrium expression for \(K_{\mathrm{a}}\). b) $$ \text { Show that } \mathrm{pH}=\mathrm{p} K_{\mathrm{a}}-\log \frac{[\mathrm{HA}]}{\left[\mathrm{A}^{-}\right]} $$