Discovery date : 1772
Discovered by : Daniel Rutherford
Origin of the name: The name is derived from the Greek 'nitron' and 'genes' meaning nitre forming.
Allotropes : N2
~>NITROGEN is a chemical element with symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772. It is the fifth most abundant element in the universe and makes up about 78% of the atmosphere of Earth.
| FACT BOX | |||
| Group | 15 | Melting point | −210.0°C, −346.0°F, 63.2 K |
| Period | 2 | Boiling point | −195.795°C, −320.431°F, 77.355 K |
| Block | p | Density (g cm−3) | 0.001145 |
| Atomic number | 7 | Relative atomic mass | 14.007 |
| State at 20°C | Gas | Key isotopes | 14N |
| Electron configuration | [He] 2s22p3 | CAS number | 7727-37-9 |
| ChemSpider ID | 20473555 | ChemSpider is a free chemical structure database | |
Nitrogen in the form of ammonium chloride, NH4Cl, was known to the alchemists as sal ammonia. It was manufactured in Egypt by heating a mixture of dung, salt and urine. Nitrogen gas itself was obtained in the 1760s by both Henry Cavendish and Joseph Priestley and they did this by removing the oxygen from air. They noted it extinguished a lighted candle and that a mouse breathing it would soon die. Neither man deduced that it was an element. The first person to suggest this was a young student Daniel Rutherford in his doctorate thesis of September 1772 at Edinburgh, Scotland.