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about is a Group 16 element. is the third most abundant element found in the sun, and it plays a part in the carbon-nitrogen cycle, one process responsible for stellar energy production. in excited states is responsible for the bright red and yellow-green colo ....

Middle of Essay
.... annually. Paradoxically, ozone is toxic! Undiluted ozone is bluish in colour. Liquid ozone is bluish-black, and solid ozone is violet-black. Oxygen is very reactive and capable of combining with most elements. It is essential for respiration of all plants and animals and for practically all combustion. history of oxygen Leonardo da Vinci suggested that air consists of at least two different gases. Before then, air was felt to be an element in its own right. He was also aware that one of these gases supported both flames and life. Oxygen was prepared by several workers before 1772 but these workers did not recognise it as an elemen ....