HCL: HCL Is a strong metallic acid, hydrolysis of hydrogen chloride gas, the percentage is 32%, using it should be done with extreme care and taking appropriate safety precaution as it is a heavy liquid, the formula is HCL and, CAS is 7647-01-0 HCL advantages are: 1. Reduce the surface of the steel to clean it from rust and iron oxides accumulated during the manufacturing process. 2. Cleaning of utensils and tools made of Stainless Steel 3. Removal of calcareous deposits from surfaces.