Cl2gas

Cl2 gas, commonly referred to as chlorine gas, is the diatomic molecule with the chemical formula Cl2. It appears as a yellow-green gas at room temperature and has a sharp, irritating odor. It is heavier than air and highly reactive, functioning as a strong oxidizer in many reactions.

Chemically, chlorine is reactive and can act as an oxidant in both inorganic and organic processes. In water, chlorine undergoes hydrolysis to form hydrochloric acid and hypochlorous acid (Cl2 + H2O ⇌ HCl + HOCl), which contributes to its disinfectant properties. It readily reacts with a wide range of organic compounds to form chlorinated products and can corrode many metals, especially in the presence of moisture.

Production and supply typically occur on an industrial scale. The principal method is the electrolysis of concentrated brine in the chlor-alkali process, which yields chlorine gas along with sodium hydroxide and hydrogen. Chlorine can also be generated in laboratory settings from various chlorine-containing reagents, but industrial electrolysis remains the primary production route.

Applications of Cl2 gas are broad. It is used for disinfecting drinking water and swimming pools, for bleaching textiles and pulp in the paper industry, and as a feedstock in the production of a wide range of organochlorine compounds, including vinyl chloride for PVC manufacture. It also serves as a chemical reagent in several synthesis pathways.

Safety and handling are critical due to its toxicity and corrosiveness. Chlorine gas can cause severe irritation and damage to the respiratory tract, eyes, and skin, with exposure potentially leading to pulmonary edema. It is stored and transported in sealed, corrosion-resistant containers and must be used with appropriate ventilation, monitoring, and personal protective equipment. Controllers and regulators establish exposure limits to minimize health risks.