Odorless white microcrystalline powder with a bitter taste. A 0.25% solution in water has a pH of 3.5 to 5.5.
Air & Water Reactions
Slightly soluble in water.
Ampicillin absorbs insignificant amounts of moisture at 77° F and relative humidities up to approximately 80%, but under damper conditions Ampicillin absorbs significant amounts. A pH-rate profile reveals specific-acid- and specific-base- catalyzed hydrolysis. The pH of maximum stability is 5.8.
Flash point data for Ampicillin are not available; however, Ampicillin is probably combustible