Oxygen atoms have 8 protons and 8 electrons. By adding two electrons to the second energy level, a more stable noble gas electron configuration is achieved by the oxygen. Since no protons are added the overall charge is -2.

When two oxygen atoms bond together to form an oxygen molecule, they share four electrons ? two from each oxygen atom. Other examples of covalent bonding are water (H2O), and carbon dioxide (CO2). Covalent compounds are usually liquids or gases with low melting points.

Two covalent bonds form between the two oxygen atoms because oxygen requires two shared electrons to fill its outermost shell. It gets these four from four hydrogen atoms, each atom providing one. These elements all share the electrons equally, creating four nonpolar covalent bonds.

An English chemist, Joseph Priestley, independently discovered oxygen in 1774 by the thermal decomposition of mercuric oxide and published his findings the same year, three years before Scheele published.

We’re observers, however, so the real trick is how oxygen gets us to pretty colors. (Actually, though it’s a colorless gas, oxygen liquefies into an attractive blue fluid.) In its gaseous form, oxygen usually doesn’t glow.

light grey

4Description. The gas is colorless, odorless, and tasteless. The liquid and solid forms are a pale blue color and are strongly paramagnetic.

Chemical Properties of Oxygen At standard temperature and pressure (STP), two atoms of the element bind to form dioxygen, a colorless, odorless, tasteless diatomic gas with the formula O2. Oxygen is a member of the chalcogen group on the periodic table and is a highly reactive nonmetallic element.

Chemical properties of oxygen – Health effects of oxygen – Environmental effects of oxygen

Free elemental oxygen occurs naturally as a gas in the form of diatomic molecules, O2 (g). Oxygen exhibits many unique physical and chemical properties. For example, oxygen is a colorless and odorless gas, with a density greater than that of air, and a very low solubility in water.

At standard temperature and pressure, hydrogen is a nontoxic, nonmetallic, odorless, tasteless, colorless, and highly combustible diatomic gas with the molecular formula H2. Hydrogen is also prevalent on Earth in the form of chemical compounds such as hydrocarbons and water.

Daniel Rutherford