1) The pair in which phosphorus atoms have a formal oxidation state of +3 is A) pyrophosphorous and hypophosphoric acids B) orthophosphorous and hypophosphoric acids C) pyrophosphorous and pyrophosphoric acids D) orthophosphorous and pyrophosphorous acids Answer: Option DExplanation: Orthophosphorous acid H3PO3 $H_{3}PO_{3}$=3+x+3(-2)=0 x= +3 Pyrophosphorous acid H4P2O5 H4P2O5=4+2x+5(-2)=0 x=+3
