# What polyatomic ion contains the greatest number of oxygen atoms?

Feb 16, 2017

See below.

#### Explanation:

The first inorganic ion I think of is the peroxodisulfate ion, $\text{S"_2"O"_8^"2-}$.

Its structure is

An important polyatomic organic ion is ATP (adenosine triphosphate).

It contains 9 oxygen atoms in the phosphate groups plus 4 more from the ribose unit.

And we must not forget DNA.

A DNA strand can contain up to 2.5 million nucleotide pairs.

Each nucleotide contains 2 oxygen atoms in the phosphate and 3 from the deoxyribose.

With 12.5 million oxygen atoms plus those in the purine and pyrimidine bases, I suppose you could say that ATP is the polyatomic ion with the most oxygen atoms.