Are polyatomic ions? Give an example each of monovalent polyatomic cation and trivalent polyatomic anion.
a) Yes; NH₄⁺ and PO₄³⁻
b) No; NH₄⁺ and PO₄³⁻
c) Yes; NO₃⁻ and SO₄²⁻
d) No; NO₃⁻ and SO₄²⁻