Why is the ionic equation for CaC2O4 = Ca2+ + C2O4 2- instead of Ca+ + C2O4-

Question

Why is the ionic equation for CaC₂O₄ = Ca²⁺ + C₂O₄^2- instead of Ca⁺ + C₂O₄^-

Answer 1

The formula for calcium oxalate is CaC₂O₄.  In its ionic state, calcium has a charge of plus 2 (calcium has two valence electrons).  The oxalate ion has a charge of minus 2.  This why the equation should be:

CaC₂O₄ --> Ca²⁺ + C₂O₄^2-