Question

Ca ---> Ca(OH)2 ---> Ca3(PO4)2

Answer 1

2Ca+2H2O = 2Ca(OH)

2H3PO4 + 3Ca(OH)2 --> Ca3(PO4)2 + 6H2O

Answer 2

1)Ca+2NaOH=Ca(OH)2+2Na

2)3Ca(OH)2+2K3PO4=Ca3(PO4)2+6KOH