Ozone is an allotrope of oxygen with chemical formula O3 and molecular formula 47.998. It is a light blue gas with fishy smell. Ozone is very oxidizing, stronger than oxygen. It can undergo oxidation reaction at a lower temperature, such as oxidizing silver into silver peroxide, oxidizing lead sulfide into lead sulfate, and reacting with potassium iodide to generate iodine. Turpentine, gas, etc. Will spontaneously ignite in ozone. Ozone is a powerful bleaching agent in the presence of water. With unsaturated organic compounds at low temperature, it is also easy to produce smelly oxides. Used as strong oxidant, bleaching agent, fur deodorizer, air purifier, disinfectant, disinfection and deodorization of drinking water. In chemical production, ozone can replace many catalytic oxidation or high temperature oxidation, which simplifies the production process and improves productivity. Liquid ozone can also be used as an oxidant for rocket fuel. It exists in the atmosphere, and its near-surface concentration is 0.00 1 ~ 0.03 ppm, which is produced by oxygen in the atmosphere absorbing ultraviolet rays with wavelength less than 185nm from the sun. This ozone layer can absorb short-wave radiation (below 30nm) harmful to human body in the sun, prevent this short-wave radiation from irradiating the ground, and protect living things from ultraviolet rays.