This compound, the aluminum salt of N-nitroso-N-phenylhydroxylamine (a derivative of Cupferron), is primarily used in analytical chemistry as a selective precipitating agent for metal ions such as copper, iron, aluminum, and others in gravimetric analysis. It forms stable chelate complexes that enable the separation and quantification of these metals from complex mixtures. Additionally, it serves as an intermediate or reagent in organic synthesis for the preparation of nitroso and hydroxylamine derivatives. Due to the presence of the N-nitroso group, it is potentially carcinogenic and should be handled with care in laboratory settings. Its niche applications make it valuable in research, environmental testing, and metallurgical analysis.