We drink chlorinated water. It is harmless, but its taste is inferior to that of spring water. Drinking water treated with ozone is absolutely free from pathogenic bacteria and has no unpleasant taste.

   Ozone can renew old automobile tyres and bleach fabrics, cellulose, and yarn. There are many other things it can do. And that is why scientists and engineers are working on the design of high-capacity industrial ozonizers.

   That is what ozone is! O₃ is no less important than O₂. Philosophy has long ago formulated the dialectical principle of the transition of quantity into quality. The example of oxygen and ozone is one of the most vivid manifestations of dialectics in chemistry.

   There is another molecule known to scientists, consisting of four oxygen atoms, O₄. However, this "quartet" is very unstable and hardly anything is known so far about its properties.

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