Dissociation of ions in acids

Arrhenius theory, theory, introduced in 1887 by the Swedish scientist Svante Arrhenius, that acids are substances that dissociate in water to yield electrically charged atoms or molecules, called ions, one of which is a hydrogen ion (H⁺), and that bases ionize in water to yield hydroxide ions (OH⁻). It is now known that the hydrogen ion cannot exist alone in water solution; rather, it exists in a combined state with a water molecule, as the hydronium ion (H₃O⁺). In practice the hydronium ion is still customarily referred to as the hydrogen ion.

Subject | Subject

​HCl -> H⁺ + Cl ^-

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2H₂O(l) ⇌ H₃O⁺(aq) + OH^-(aq)​

H₂O(l) ⇌ H⁺(aq) + OH^-(aq)​​

Dissociation of ions in acids

In short...

An acid is a substance that increases the concentration of hydrogen ions in a solution.

An alkali is a substance that increases the concentration of hydroxide ions ​in a solution.

Subject | Subject

​HCl -> H⁺ + Cl ^-

​

2H₂O(l) ⇌ H₃O⁺(aq) + OH^-(aq)​

H₂O(l) ⇌ H⁺(aq) + OH^-(aq)​​

Not all acids are the same.

Let us compare the difference between hydrochloric acid and ethanoic acid (Vinegar)​

​Are all acids the same?

Strong acid is an acid that is completely ionised in aqueous solution.

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​A weak acid is an acid that is only partially ionised in an aqueous solution.

​​Strength of acid

Concentration is the number of moles of an acid per unit volume.

​​Concentration of acid