Nitrate is a polyatomic ion, meaning it's a group of atoms bonded together with a net charge. It's represented as NO₃⁻.

Atomic numbers refer to individual elements. Therefore, nitrate doesn't have an atomic number.

You can, however, consider the atomic numbers of the elements that make up nitrate:

* Nitrogen (N): Atomic number 7

* Oxygen (O): Atomic number 8

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