Oxygen (O)
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Physical properties
Oxygen has some physical properties such as the melting point of -361.9 (f) or -619.42 (c). Another property is the boiling point of -297.3 (f) or 183 (c). Oxygen is also a colorless, tasteless, and odorless element.
Chemical Properties
Oxygen usually has the oxidation state at -2. When oxygen mixes with hydrogen you get water or H2O. This happens by also heating them up. And oxygen is a non toxic element.
Compounds
Oxygen is an element with the symbol of O. When one element is combined with another it is called a compound. Oxygen with carbon would be OC, oxygen with iron would be OFe, and oxygen with hydrogen would be OH. Most people have heard of H20. All the two means is that there are two hydrogen's in that compound. If you have carbon and want to make some water, buying some of my Oxygen would be very beneficial.
Isotopes
An isotope is when an element has a different number of neutrons then normal. For this to happen the mass has to change. Oxygen would have more neutrons if it had a mass of 17 vs a mass of 16.