how is it stored?
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oxygen (o2) is formed in photosynthesis as a direct result of Light-driven splitting of water during oxygenic photosynthesis how does lavoisier contribute? He conducted the first adequate quantitative experiments on oxidation and gave the first correct explanation of how combustion works what are its isotopes? They are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number what are its allotropes? UNANSWERABLE
Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds High pressure oxygen tanks, cryogenics and chemical compounds. In high pressure oxygen tanks, cryogenics and chemical compounds.
Oxygen Oxygen Oxygen
Storage Storage Storage
Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds.  Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds. 
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Isotope [SEP] Introduction
Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom. The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by a Scottish doctor and writer Margaret Todd in 1913 in a suggestion to chemist Frederick Soddy.