What are polyatomic ions?

1 Answer
Jun 26, 2016

Polyatomic ions are molecular species that happen to have a charge, an excess or deficiency of electrons; e.g. #NO_3^(-), ClO_4^(-), SO_4^(2-)#.

Explanation:

Take the neutral oxygen molecule, #O=O#, add 2 electrons, and we have the peroxide ion, #""^(-)O-O^-#. Of course, this species is associated with #K^+#/#Na^+# counterions; how many?