The mass of an atom comes from the protons and neutrons
that are found in the nucleus. The number of protons is the atomic number of an
element. To find the number of neutrons, subtract the atomic number from the
mass of an atom. The atomic number is 8 and the atomic mass is 16.
Answer:
2H3PO4 +3Ca(OH) 2 = Ca3 (PO4) 2 +6H20