Glad to hear that everyone has been enjoying the series thus far. Now we've now come to element number 7: Nitrogen.
Nitrogen belongs to group 15 (the pnictogens) and has the elemental symbol N, atomic number 7, a mass of 14.01 amu, and electron configuration of [He] 2s2 2p3. Nitrogen was discovered in 1772 by Daniel Rutherford.
Nitrogen is generally found as diatomic gas N2 which makes up about 79% of the earth's atmosphere. Nitrogen is pretty common in the universe, and is fairly volatile. When not found in gaseous form, Nitrogen is often bonded to oxygen or hydrogen. Nitrogen is essential in the formation of some important organic compounds such as amino acids (and thus proteins), and the purine/pyrimidine bases of DNA and RNA. Inorganic nitrogen ions are essential for plant life, most notably nitrates. Certain bacteria can 'fix' atmospheric nitrogen, into the more soluble form of nitrates, which is used by plants.
*I once had ice cream made with liquid Nitrogen, it was amazing to watch them make it.