The magic of dioxygen.

Oxygen has to be considered one of the most important elements on Earth. Earlier, some dispute arose as to which of the three scientists, Carl Wilhelm Scheele (Sweden), Joseph Priestley (United Kingdom) or Antoine Lavoisier (France), should get credit for the air of life.Today it is agreed that the Swede discovered it first, the fire air in 1772. The British chemist published it first, the dephlogisticated air in 1775, and the Frenchman understood it first, the oxygen in 1775-1778. Surely, there is credit enough for all three to split the "Nobel Prize" awarded by Carl Djerassi and Roald Hoffmann in their play Oxygen. Molecular oxygen means life. So-called aerobes - these include humans, animals, and plants - need O2 to conserve the energy they have to gain from their environment. Eliminate O2 and these organisms cannot support an active lifestyle. What makes dioxygen that special? It is a non-metal and oxidizing agent that readily reacts with most elements to form compounds, notably oxides. From a biological point of view, the most important compound of course is water, H2O, which provides an excellent solvent for biomolecules. It influences the climate of the Earth, and it is the source of almost all of the molecular oxygen in the atmosphere.