Chapter 16

Malonic acid \(\left[\mathrm{CH}_{2}(\mathrm{COOH})_{2}\right]\) is a diprotic acid. Explain what that means.

Write all the species (except water) that are present in a phosphoric acid solution. Indicate which species can act as a Bronsted acid, which as a Bronsted base, and which as both a Bronsted acid and a Bronsted base.

What are the concentrations of \(\mathrm{HSO}_{4}^{-}, \mathrm{SO}_{4}^{2-},\) and \(\mathrm{H}^{+}\) in a \(0.20 \mathrm{M} \mathrm{KHSO}_{4}\) solution? (Hint: \(\mathrm{H}_{2} \mathrm{SO}_{4}\) is a strong acid: \(K_{\mathrm{a}}\) for \(\left.\mathrm{HSO}_{4}^{-}=1.3 \times 10^{-2} .\right)\)

Calculate the concentrations of \(\mathrm{H}^{+}, \mathrm{HCO}_{3}^{-},\) and \(\mathrm{CO}_{3}^{2-}\) in a \(0.025 \mathrm{M} \mathrm{H}_{2} \mathrm{CO}_{3}\) solution.

Write the equation relating \(K_{\mathrm{a}}\) for a weak acid and \(K_{\mathrm{b}}\) for its conjugate base. Use \(\mathrm{NH}_{3}\) and its conjugate acid \(\mathrm{NH}_{4}^{+}\) to derive the relationship between \(K_{\mathrm{a}}\) and \(K_{\mathrm{b}}\).

The pH of a \(0.30 M\) solution of a weak base is 10.66 . What is the \(K_{\mathrm{b}}\) of the base?

List four factors that affect the strength of an acid.

How does the strength of an oxoacid depend on the electronegativity and oxidation number of the central atom?

Predict the acid strengths of the following compounds: \(\mathrm{H}_{2} \mathrm{O}, \mathrm{H}_{2} \mathrm{~S},\) and \(\mathrm{H}_{2} \mathrm{Se} .\)

Compare the strengths of the following pairs of acids: (a) \(\mathrm{H}_{2} \mathrm{SO}_{4}\) and \(\mathrm{H}_{2} \mathrm{SeO}_{4},\) (b) \(\mathrm{H}_{3} \mathrm{PO}_{4}\) and \(\mathrm{H}_{3} \mathrm{AsO}_{4}\).