Use boiling water to remove scale (chemical equation) CaCO3 + 2HCl = CaCl2 + H2O + CO2 ↑ and Mg (OH) 2 + 2HCl = MgCl2 + 2H2O) laboratory preparation of carbon dioxide (chemical formula): CaCO3 + 2HCl = CaCl2 + H2O + CO2 ↑ hydrochloric acid and physical properties of iron, magnesium and other metals produced by the reaction of a small amount of hydrogen required chemistry experiment (chemical equation is: 2HCl = FeCl2 + H2 ↑ Fe (Mg) +) each department uses (a) Industrial hydrochloride in the national economy hydrochloride laboratory system of law, the use of hydrochloric acid is widely described as follows: (1) for the rare metal hydrometallurgical (2) used in organic synthesis (3) for the dyeing industry (4) metalworking (5 ) for the food industry (6) Hydrochloride just some examples of the industrial production of organic and inorganic chemicals and drugs used in the production of the above-listed. In fact hydrochloric security, but also a lot of use of hydrochloric acid. Hydrochloric acid in everyday life, we sometimes also use it, for example the lack of stomach acid, indigestion, the doctor gave us a certain amount of dilute hydrochloric acid to supplement stomach acid. In chemical experiments and scientific research, use of hydrochloric acid in the place even more. Hydrochloric acid, prepared by the laboratory of chemical _ _ Zhengzhou Zhongyuan District Long hydrochloric acid provided by the Zhengzhou Longda Chemical Products Limited. Zhengzhou Longda Chemical Products Co., Ltd. (www.longdahuagong.com/) is located in Hi-tech District, Zhengzhou City, Henan Province Chemical Road 99 (Chemical Road and Rita Road intersection 100 meters south west). Scraps and development in the wave of market economy, the current Zhengzhou Longda Chemical has a high reputation in inorganic acids, enjoy a good reputation. Zhengzhou Longda Chemical acquired the whole network business alliance certification, marking our service and management level has reached a new height. Zhengzhou Longda Chemical staff willing to work with all people of insight and common development, for a better future.