P→Ca3P2→PH3→P2O5→Na3PO4→Ag3PO4
2P+3Ca=Ca3P2
Ca3P2+6H20= 3Ca(OH)2+2PH3
2PH3+5H20=P2O5+8H2
P2O5+3Na2O=2NA3PO4
NA3PO4+3AgCL= 3NaCL+Ag3PO4