This heterocyclic building block, also known as 1,10-phenanthroline hydrate, presents as a white to pale yellow red, odorless crystalline powder. It is known to be soluble in alcohols, benzene and acetone and very slightly soluble in ether and water. Store in a cool and dark place, under inert gas and protected from moisture. 1,10-Phenanthroline is incompatible with oxidizing agents and toxic if swallowed. It is also very toxic to aquatic life.