1.0 grams of a sample containing phosphorus was dissolved into PO43- and the sample was diluted to 500 mL with distilled water. 25.0 mL of 0.07521 M AgNO3 solution was added on the 100.0 mL portion of this solution and all of the phosphorus was precipitated as Ag3PO4. If the remaining AgNO3 is back-titrated with 5.2 mL 0.0585 M KSCN in the presence of Fe3+ indicator, calculate the phosphorus in the sample a) as % P b) as % P2O5? (g / mol: P = 31; O = 16)

a) as % P b) as % P2O5? (g/mol: P = 31; 0 = 16) Precipitation reaction: P02% + 3Ag* Ag3PO4 (S); Titration reaction: Agt +SCN AgSCN (s)