0=16] atomic See also:

• WEIGHT

weight 14.01 See also:

• 0=16] atomic weight 14.01 NITROGEN [symbol N.

NITROGEN [See also:

• SYMBOL (Gr. o-uµ(3oXov, a sign)

symbol N.  . A non-metallic chemical See also:

• ELEMENT (Lat. elementum)

element, first isolated in 1772 by D . See also:

• RUTHERFORD, MARK
• RUTHERFORD, WILLIAM GUNION (1853–1907)

Rutherford, who showed that on removing See also:

• OXYGEN (symbol 0, atomic weight 16)

oxygen from See also:

• AIR (from an Indo-European root meaning " breathe," " blow ")
• AIR, or ASBEN

air a See also:

• GAS

gas remained, which was incapable of supporting See also:

• COMBUSTION (from the Lat. comburere, to burn up)

combustion or respiration . See also:

• NITROGEN [symbol N., atomic weight 14.01, 0=16]

Nitrogen forms approximately 79% by See also:

• VOLUME

volume (or 77% by See also:

• WEIGHT

weight) of the See also:

• ATMOSPHERE (Gr. fir µ6r, vapour; orkaipa, a sphere)

atmosphere; actual values are: % by volume—79.07 (See also:

• REGNAULT, HENRI (1843-1871)
• REGNAULT, HENRI VICTOR (1810-1878)
• REGNAULT, JEAN BAPTISTE (1754-1829)

Regnault), 79.20 (See also:

• DUMAS, ALEXANDRE
• DUMAS, ALEXANDRE [" DUMAS FILS"] (1824-1895)
• DUMAS, GUILLAUME MATHIEU, COUNT (1753-1837)
• DUMAS, JEAN BAPTISTE ANDRE (1800-1884)

Dumas); %by weight—76.87 (Regnault), 77.00 (Dumas), 77.002 (Levey), 76.900 (See also:

• STAS, JEAN SERVAIS (1813–1891)

Stas), 77.010 (See also:

• MARIGNAC, JEAN CHARLES GALISSARD DE (1817-1894)

Marignac) . No absolutely accurate determinations appear to have been made recently . See also:

• FREE

Free nitrogen is also found in some natural See also:

• WATERS, TERRITORIAL

waters and has been recognized in certain nebulae . In the combined See also:

• STATE
• STATE, GREAT OFFICERS OF

state nitrogen is fairly widely distributed, being found in See also:

• NITRE

nitre, See also:

• CHILE, or CHILI (derived, it is said, from the Quichua chin , cold, or tchili, snow)

Chile See also:

• SALTPETRE (from the Lat. sal, salt, Petra, a rock)

saltpetre, ammonium salts and in various See also:

• ANIMAL
• ANIMAL (Lat. animalis, from anima, breath, soul)

animal and See also:

• VEGETABLE

vegetable tissues and liquids . It is invariably See also:

• PRESENT

present in soils, where compounds are formed by nitrifying bacteria . Nitrogen may be obtained from the atmosphere by the removal of the oxygen with which it is there mixed . This may be effected by burning See also:

• PHOSPHORUS (Gr. 4ws, light, sPEpety, to bear)

phosphorus in a confined volume of air, by the See also:

• ACTION

action of an alkaline See also:

• SOLUTION (from Lat. solvere, to loosen, dissolve)

solution of See also:

• PYROGALLOL, or PYROGALLIC ACID

pyrogallol on air, by passing air over heated See also:

• COPPER (symbol Cu, atomic weight 63.1, H=1, or 63.6, O = 16)

copper, or by the action of copper on air in the presence of ammoniacal solutions . It is also prepared by See also:

• HEATING

heating ammonium nitrite (or a mixture of See also:

• SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium nitrite and ammonium chloride): NH4NO2=2H20+N2; by heating a mixture of ammonium nitrate and chloride (the See also:

• CHLORINE (symbol Cl, atomic weight 35`46 (0=16)

chlorine which is simultaneously produced being absorbed by See also:

• MILK (0. Eng. meoluc; from a common Indo-European root, cf. Lat. mulgere, Gr. ?t dXyetv)

milk of See also:

• LIME
• LIME (O. Eng. lim, Lat. limes, mud, from linere, to smear)

lime orby a solution of sodium hydroxide) : 4NH4NO3+2NH4CI =5N2 +C12+12H20; by heating ammonium dichromate (or a mixture of ammonium chloride and See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium dichromate) : (NH4)5Cr2O7 =Cr203+4H2O+N2; by passing chlorine into a concentrated solution of See also:

• AMMONIA (NH3)

ammonia (which should be present in considerable excess) : 8NH3+3C12=6NH4Cl+N2; by the action of hypochlorites or hypobromites on ammonia: 3NaOl3r±2NH3=3NaBr+3H20+N2; and by the action of See also:

• MANGANESE (symbol Mn; atomic weight, 54.93 (0=16)], a metallic chemical element. Its dioxide (pyrolusite)

manganese dioxide on ammonium nitrate at 180-200° C . It is also formed by the reduction of nitric and nitrous oxides with See also:

• HYDROGEN [symbol H, atomic weight x-oo8 (0=16)]

hydrogen in the presence of platinized See also:

• ASBESTOS

asbestos at a red See also:

• HEAT (0. E. haktu, which like " hot," Old Eng. hat, is from the Teutonic type haita, hit, to be hot; cf. Ger. hitze, heiss; Dutch, hitte, heet, &c.)

heat (G. v .

Knorre and K . See also:

• ARNDT, ERNST MORITZ (1769-1860)
• ARNDT, JOHANN (1555-1621)

Arndt, Ber., 1899, 32, p . 2136) ; by the oxidation of See also:

• HYDROXYLAMINE, NH2OH

hydroxylamine (ibid., 1900, 33, p . 30) ; and by the See also:

• ELECTROLYSIS (formed from Gr. Xbety, to loosen)

electrolysis of See also:

• HYDRAZINE (DIAMIDOGEN), N2H4

hydrazine and its salts (E . Ch . Szarvasy, Jour . Chem . See also:

• SOC

Soc., 1900, 77, p . 603) . The See also:

• CHIEF (from Fr. chef, head, Lat. caput)

chief importance of nitrogenous compounds depends upon their assimilation by living See also:

• PLANTS

plants, which, in their development, absorb these compounds from the See also:

• SOIL

soil, wherein they are formed mainly by the action of nitrifying bacteria . Since these compounds are essential to plant See also:

• LIFE

life, it becomes necessary to replace the amount abstracted from the soil, and hence a demand for nitrogenous See also:

• MANURES

manures was created . This was met in a very large measure by deposits of natural nitre and the products of artificial nitrieres, whilst additional supplies are available in the ammoniacal liquors of the gas-manufacturer, &c .

The possible failure of the nitre deposits led to attempts to convert atmospheric nitrogen into manures by processes permitting economic success . See also:

• COMBINATION (Lat. combinare, to combine)

Combination can be made in five directions, viz. to See also:

• FORM (Lat. forma)

form (1) oxides and nitric acids, (2) ammonia, (3) readily decomposable nitrides, (4) cyanides, (5) cyanamides .