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How does acetic acid dissociate when dissolved in water?

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sodium sulfate — acid–base reaction Sodium sulfate, also called Glauber's salt, is, like other salts, the product of an acid-base reaction.

When acetic acid is dissolved in water, it undergoes dissociation by donating a proton ( $H^{+}$ ) to a water molecule, which acts as a base. This process is represented by the following equilibrium equation:

CH $_{3}$ CO $_{2}$ H + H $_{2}$ O ⇌ CH $_{3}$ CO $_{2}^{-}$ + H $_{3}$ O $^{+}$ 1

In this reaction, the acetic acid molecule loses a proton to become a negatively charged carboxylate ion, specifically an acetate ion (CH $_{3}$ CO $_{2}^{-}$ ), while the water molecule gains the proton to form a hydronium ion (H $_{3}$ O $^{+}$ ).12

The extent of this dissociation is governed by the dissociation constant ( $K_{a}$ ), which for acetic acid is 1.76 × 10 $^{- 5}$ at 25 °C. Because acetic acid is a weak acid, it does not dissociate completely in water; the degree of dissociation depends on the concentration of the solution, with the fraction of dissociated acid increasing as the concentration decreases.3