Question

a polyatomic ion has the formula c₂h₃o₂⁻. what is the name of this ion?

Explanation:

The polyatomic ion with the formula \( \ce{C2H3O2^-} \) is the acetate ion (or sometimes called ethanoate ion, but acetate is the common name). It is derived from acetic acid (\( \ce{CH3COOH} \)) when it loses a proton (\( \ce{H^+} \)), forming \( \ce{CH3COO^-} \) (which is equivalent to \( \ce{C2H3O2^-} \) in terms of atom count and charge).

Answer:

acetate ion (or ethanoate ion)