If you had 6 moles of CaCl2 and 5 moles of Na3PO4, which of these would be the limiting and excess reactant

Na3PO4 is excess reactant, CaCl2 is limiting reactant.

Explanation:

                                      3CaCl2 + 2Na3PO4 ---> Ca3(PO4)2 + 6NaCl

from reaction :              3 mol        2 mol

given:                            6 mol         5 mol (X)

X = (6*2)/3 = 4 mol Na3PO4

For 6 mol CaCl2 we need 4 mol Na3PO4, but  we have 5 mol Na3PO4,

Na3PO4 is excess reactant, so CaCl2 is limiting reactant.

a chemical reaction

explanation: