$\mathrm{Na}^{+}$

$\mathrm{Sr}^{2+}$

$\mathrm{Mg}^{2+}$

$\mathrm{Ca}^{2+}$

Valine

Proline

Tyrosine

Alanine

Action of $\mathrm{NH}_2 \mathrm{OH}$ to form oxime

Heating with HI forming $n$-hexane

Formation of pentaacetate derivative when reacted with acetic anhydride

Glucose and gluconic acid both form saccharic acid when treated with dilute $\mathrm{HNO}_3$

Proline

Phenylalanine

Methionine

Valine