P->P2O5->K3PO4->Ca3(PO4)2->P->Ca3P2

Question

P->P2O5->K3PO4->Ca3(PO4)2->P->Ca3P2

Answer 1

4P+5O2=2P2O5

6KOH(изб)+P2O5=2K3PO4+3H2O

3CaCl2+2K3PO4=Ca3(PO4)2(осадок)+6KCl

Ca3(PO4)2+5C+3SiO2=2P+3CaSiO3+5CO

4P+3Ca2->2Ca3P2