Complex sentence: It is commonly used in the determination of phosphate ions as ammonium molybdovanadate with the addition of 70% perchloric acid (sulphuric acid is also known to be used).
Split into simpler sentences: It is commonly used in the determination of phosphate ions. The reagent used is ammonium molybdovanadate with the addition of 70% perchloric acid (sulphuric acid is also known to be used).