The chemical element Nitrogen (N symbol in the periodic table) was discovered in 1772, by Daniel Rutherford, a Scottish physician. The origin of the name "nitrogène" was from a suggestion from a French chemist named Jean Antoine Claude Chaptal in 1790, this was due to the fact that it was present both in nitric acid and nitrates. Another chemist named Antoine Lavoisier suggested "azote" from Greek ἀζωτικός meaning "no life" because it is an asphyxiant gas. It can also be called "pnictogens" in the periodic table of elements and comes from the Greek πνίγειν meaning "to choke."
Nitrogen's atomic number is 7 and is in group 15 in the periodic table. It is also the lightest member of that group. When at standard temperature and pressure, two atoms bind to form "dinitrogen" (formula N2) which is an odorless and colorless diatomic gas that forms 78% of earth's atmosphere and is said to be the most abundant uncombined element. It also has one of the highest electronegativities among the elements (Pauling scale of 3.04).
Nitrogen can be found in all organisms (3% of nitrogen is contained in the human body) and can be found also in nucleic acids (DNA and RNA), amino acids, and energy transfer molecule adenosine triphosphate. Plants nor animals can absorb nitrogen directly, it must go through a process to become converted into compounds, this is called the Nitrogen Cycle.
There are about 4 steps in this cycle:
Step 1 is called Nitrogen Fixation. This is when special bacteria convert into nitrogen gas ( N2 ) and into (NH3) ammonia. Nitrogen Fixation discovered by Beijerinck in 1901.
Step 2 is Nitrification and is a process which converts ammonia into nitrite ions (plants also can use this to take as nutrients).
Step 3 is Ammonification, this happens once organisms have used all the nitrogen and then decomposing bacteria converts the nitrogen waste compounds into simpler compounds.
And lastly, step 4 is Denitrification, this is when other bacteria convert simple nitrogen compounds back as nitrogen gas ( N2 ) , and then the process begins once again.
Plants need nitrogen for plant growth and also produced and is a critical component of many aquatic, as well as the terrestrial ecosystem. An article in Nature Education Knowledge had shown their results of growing plants with and without Bradyrhizobia (Gram-negative soil bacteria) showing that plants without the bacteria were lighter in color. The study was done to see the effects of nitrogen 's role (in fertilizers).
The atoms of nitrogen have seven electrons. Their configuration in the ground state is 1s2
2s2
2p1
x2p1
y2p1
z. Meaning it has 5 valences electrons within the 2s and 2p orbitals (3 of them are pre-electrons and are unpaired). It also has two stable isotopes (14N and 15N.) 14N is more common, which makes up 99.634% of natural nitrogen, with only 15N having 0.366% and which is also slightly heavier than 14N. Both conclude to an atomic weight of 14.007 u.
Nitrides can be used in different oxidations from +1 to +5 to for oxide compounds. Oxides are acidic and can become attached to protons and most forms are of gasses and can exist at 25°C. Although they play a major part in living organisms, it can also be dangerous.
Hydrides of nitrogen include that of ammonia (NH3) and hyrdrazine (N2H4). H yrdrazine is used mostly as rocket fuel, and ammonium ions have special amphiprotic properties.
Ammonia was developed between 1909 to 1913 by Fritz Haber. His mixture was of N2 and H2 gas at 200 to 300 atm and 400 to 600oC is passed over a catalyst of finely divided iron.
Fe N2(g)+3 H2(g)---->2 NH3(g)
Another development was that of the use of hypochlorite (OCl-) ion to oxidize ammonia to produce hydrazine, N2H4.
NH3(aq) +OCl-(aq)---->N2H4(aq)+Cl-(aq)+H2O(l)
Nothing of OCI- ion is of two electron oxidizing agent. Loss of electrons and a pair of H+ ions next to NH3 molecules would build a pair of reactive N2 molecules.
mechanism
Above is the hydrazine molecule. It is a colorless liquid with a hint of ammonia odor.
- Medical
Nitrogen in most cases of use is for the preservation of tissue samples, blood (and blood components), body fluids, and other cells. Liquid nitrogen can also be used for tissue, warts, and also small cancer removal.
Depending on the use, Nitrogen can be in the form of dry ice or liquid. Dry ice is a chemical formula is the same as carbon dioxide (CO2 ). When the gas is frozen it is then called dry ice.
Liquid nitrogen needs to be cooled extensively, around -346°F. Below this temperature, it can form into a solid. Above -320.44°F, it becomes gas again. Liquid nitrogen is colder than dry ice and can be dangerous.