Question

What is the chemical equation for $ HCl $ dissolving into water and ionizing?

Answer 1

Hint :We know that hydrogen chloride is a covalently bonded molecule which generally exists as a gas. When added in water it ionizes forming a proton and chloride ion. You must recall the preparation of hydrogen chloride in the laboratory in order to answer this question.

Complete Step By Step Answer:
Direct absorption of hydrogen chloride gas in water is not feasible as direct absorption leads to the back suction of water. It is caused when the rate of absorption exceeds the rate of production of the hydrogen chloride gas. Thus, a low pressure is created in the flask causing the water to be pulled into the reaction. Hydrochloric acid is prepared by dissolving hydrogen chloride and water. When hydrogen chloride gas enters the water, the water molecules take the hydrogen atom in $ HCl, $ and pull it away from the chlorine atom. This is the dissolution process, which makes hydrochloric acid.
Hydrochloric acid, $ HCl, $ is a strong acid, so right from the start you should expect it to ionize completely in aqueous solution. In other words, every molecule of hydrochloric acid that is added to water will donate its proton, H+, to water molecule to form a hydronium cation, $ {{H}_{3}}{{O}^{+}}. $ Hydrochloric acid's ionization will also produce chloride anions, $ C{{l}^{-}}. $
 $ HC{{l}_{(aq)}}+{{H}_{2}}{{O}_{(l)}}\to {{H}_{3}}O_{(aq)}^{+}+Cl_{(aq)}^{-} $
Hydrogen chloride is also generated as by-products from industrial-scale production of other chemicals. Industrially it is prepared by the combustion of hydrogen in chlorine. Due to evaporation, the high concentration of $ HCl $ is hard to prepare.

Note :
Most of the hydrogen chloride produced industrially is for the production of hydrochloric acid. At large scale, hydrogen chloride is produced by directly combining hydrogen gas and chlorine gas. The reaction is highly exothermic and a great amount of heat is produced. The gas produced is then absorbed into water forming pure hydrochloric acid.