Hydrochloric acid (hydrochloric acid, hydrochloric acid, E507) is a solution of hydrogen chloride in water, a strong monobasic acid. The chemical formula is HCl.
Colorless,” smoking ” in the air, highly caustic liquid (technical hydrochloric acid is yellowish due to impurities of Fe, Cl2, etc.). The maximum concentration at 20 °C is 38% by weight, the density of such a solution is 1.19 g /cm3. Weak solutions of hydrochloric acid (up to 0.4 %) have a specific tart-sour taste, more concentrated ones cause burns of the oral cavity. Salts of hydrochloric acid are called chlorides.
In the food industry, it is registered as an acidity regulator. It is used for the production of seltzer (soda) water.
Hydrochloric acid is a caustic substance that causes severe burns when it gets on the skin. Especially dangerous is contact with the eyes. When opening the vessels with hydrochloric acid under normal conditions, fog and hydrogen chloride vapors are formed, which irritate the mucous membranes and respiratory tract.
Reacting with substances such as bleach, manganese dioxide, or potassium permanganate, it forms toxic chlorine gas.