What is a polyatomic ion?

Question

what do i need to know about them.

Answer 1

A polyatomic ion is a group of nonmetallic atoms covalently bonded to each other. This group of atoms carries an over-all positive or negative electric charge.

In simpler terms, a polyatomic ion is a group of atoms that are joined and generally remain joined together during a chemical reaction. The group has extra electrons which give it a negative charge (except for ammonium NH4 1+ which has lost an electron to have a net positive charge).

Examples are: nitrate = NO3 1-; sulfate = SO4 2-; carbonate = CO3 2-; hydroxide = OH 1-

Answer 2

Polyatomic ions are electrically charges collections of two or more atoms Polyatomic ions usually have a charge because the collection of atoms has either gained an extra electron or else it has lost an electron.