Answer:
Charge on Phosphate is -3 (PO₄³⁻)
Explanation:
Ions or polyatomic ions are formed when an atom or molecule loses or gains electron(s) respectively.
Example:
Formation of ions.
Na → Na⁺ + e⁻ (Na loses one electron)
Cl₂ + 2 e⁻ → 2 Cl⁻ (Cl gains electron)
In polyatomic ions a charge is present on a molecule which has either two or more atoms.
Example:
CO₃²⁻ , SO₄⁻ , NH₄⁺ e.t.c.
In statement the K₃PO₄ polyatomic ionic compound. It is made up of three K⁺ ions and one Phosphate ion (PO₄ˣ⁻) ion.
As we know K belongs to group 1 metals so it has one valence electron and thus, forms a cation of +1 charge. So, for a neutral polyatomic ionic compound the overall charge on K₃PO₄ should be zero. Hence,
K (3) + PO₄ (X) = 0
Or,
+3 + X = 0
Or,
X = 0 - 3
X = -3
Therefore, the charge on phosphate is -3.