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The normal pH range for blood plasma is 7.35 to 7.45 Under these conditions, would you expect the carboxyl group of lactic acid \(\left(\mathrm{p} K_{\mathrm{a}} 4.07\right)\) to exist primarily as a carboxyl group or as a carboxylate anion? Explain.

The \(p K_{a}\) of ascorbic acid (Vitamin \(C\), see Chemical Connections \(19 \mathrm{B}\) ) is \(4.10 .\) Would you expect ascorbic acid dissolved in blood plasma, pH \(7.35-7.45,\) to exist primarily as ascorbic acid or as ascorbate anion? Explain

Which is the stronger base: \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{NH}_{2}\) or \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COO}^{-} ?\) Explain.

Define and give an example of Fischer esterification.

Methyl 2-hydroxybenzoate (methyl salicylate) has the odor of oil of wintergreen. This compound is prepared by Fischer esterification of 2-hydroxybenzoic acid (salicylic acid) with methanol. Draw a structural formula for methyl 2-hydroxybenzoate.

Give the expected organic product formed when phenylacetic acid, \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{COOH}\), is treated with each of the following reagents: (a) \(\mathrm{NaHCO}_{3}, \mathrm{H}_{2} \mathrm{O}\) (b) \(\mathrm{NaOH}, \mathrm{H}_{2} \mathrm{O}\) (c) \(\mathrm{NH}_{3}, \mathrm{H}_{2} \mathrm{O}\) (d) \(\operatorname{LiAlH}_{4}\) then \(\mathrm{H}_{2} \mathrm{O}\) (e) \(\mathrm{NaBH}_{4}\) then \(\mathrm{H}_{2} \mathrm{O}\) \((\mathrm{f}) \quad \mathrm{CH}_{3} \mathrm{OH}+\mathrm{H}_{2} \mathrm{SO}_{4}\) (catalyst) \((g) \quad H_{2} / N i\)

When 5 -hydroxypentanoic acid is treated with an acid catalyst, it forms a lactone (a cyclic ester), Draw a structural formula for this lactone.