= Glycolate
\b[Glycolate], also called hydroxyacetate, is the <conjugate base> of <glycolic acid>. Its connectivity is $\mathrm{HOCH_2COO^-}$, with <molecular formula> $\mathrm{C_2H_3O_3^-}$ and net charge $-1$. ChEBI explicitly distinguishes this anion from its neutral acid.<Glycolate in ChEBI>[CHEBI:29805, structure, formula, charge and conjugate-base relation]{ref}
Removing the carboxyl proton changes both hydrogen count and charge:
$$
\mathrm{HOCH_2COOH}\rightleftharpoons\mathrm{H^+}+\mathrm{HOCH_2COO^-}.
$$
The alcohol-like <hydroxy group> remains in the specified singly charged species. Formula bookkeeping must therefore distinguish the acid, the anion and a complete <salt> containing the anion.
For example, one monovalent positive <counterion> balances one glycolate, while a divalent positive counterion requires two. A nominal calcium glycolate formula is $\mathrm{Ca(C_2H_3O_3)_2}$. An original amount example with $1\,\mathrm{mmol}$ of that formula unit contains $2\,\mathrm{mmol}$ of glycolate units. Hydration or another salt form changes formula mass and sample composition, so the mass of the isolated anion is not a universal salt molar mass.
Acid–base equilibrium determines how much is present as glycolate. For a suitable dilute-solution model,
$$
\frac{[\mathrm{glycolate}]}{[\mathrm{glycolic\ acid}]}\simeq10^{\mathrm{pH}-\mathrm{p}K_a}.
$$
At $\mathrm{pH}=\mathrm{p}K_a$ the two forms have equal modeled concentrations; one pH unit above gives a $10:1$ ratio and base fraction $10/11\simeq0.909$. This relative example does not assign a numerical <acid dissociation constant>. Activities, ionic strength and other equilibria matter when the dilute approximation is inadequate.
The chemical identity is independent of whether the ion was prepared as a salt or produced by deprotonating the acid in solution. An analysis that measures total glycolic-acid-derived material must state whether its reported quantity includes both protonation states or specifically the glycolate anion.
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