See also:

• COLUMBIUM, or NIOBIUM (symbol Cb or Nb, atomic weight 94)

COLUMBIUM, or NIOBIUM (See also:

• SYMBOL (Gr. o-uµ(3oXov, a sign)

symbol Cb or Nb, atomic See also:

• WEIGHT

weight 94)  , one of the metallic elements of the See also:

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

nitrogen See also:

• GROUP

group, first detected in 18or by C . Hatchett in a specimen of See also:

• COLUMBITE

columbite (niobite) from See also:

• MASSACHUSETTS (an Indian name, originally applied to a tribe of Indians)

Massachusetts (Phil . Trans . 1802, 49) . It is usually found associated with See also:

• TANTALUM [symbol Ta, atomic weight 181•o (0=16)]

tantalum, the See also:

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

chief minerals containing these two elements being tantalite, columbite, fergusonite and yttrotantalite; it is also a constituent of pyrochlor, euxenite and samarskite . See also:

• COLUMBIUM, or NIOBIUM (symbol Cb or Nb, atomic weight 94)

Columbium compounds are usually prepared by fusing columbite with an excess of See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid See also:

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

potassium sulphate, boiling out the fused See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass with much See also:

• WATER

water, and removing See also:

• TIN (Lat.- stannum, whence the chemical symbol " Sn "; atomic weight =117.6, 0=16)

tin and See also:

• TUNGSTEN [symbol W, atomic weight 184.o (0=16)]

tungsten from the See also:

• RESIDUE (through the French, from the Lat. residuum, a remainder, from residere, to remain)

residue by digestion with ammonium sulphide, any See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron See also:

• PRESENT

present being simultaneously converted into ferrous sulphide . The residue is washed, extracted by dilute hydrochloric acid, and again well washed with boiling water . It is then dissolved in hydrofluoric acid and heated in See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order to expel See also:

• SILICON [symbol Si, atomic weight 28.3 (0= 16)]

silicon fluoride; finally the columbium, tantalum and See also:

• TITANIUM [symbol Ti, atomic weight 48.1 (0 = 16)]

titanium fluorides are separated by the different solubilities of their See also:

• DOUBLE
• DOUBLE (from the Mid. Eng. duble, the form which gives the present pronunciation, through the Old Er. duble, from Lat. duplus, twice as much)

double fluorides (C . See also:

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

Marignac, See also:

• ANN

Ann. chim. et phys. x866 [41, 8, p . 63; 1868, 13, p . 28; see also W . See also:

• GIBBS, JOSIAH WILLARD (1839-1903)
• GIBBS, OLIVER WOLCOTT (1822-1908)

Gibbs, Jahresb .

1864, p . 685; R . D . See also:

• HALL
• HALL (generally known as SCHWABISCH-HALL, tc distinguish it from the small town of Hall in Tirol and Bad-Hall, a health resort in Upper Austria)
• HALL (O.E. heall, a common Teutonic word, cf. Ger. Halle)
• HALL, BASIL (1788-1844)
• HALL, CARL CHRISTIAN (1812–1888)
• HALL, CHARLES FRANCIS (1821-1871)
• HALL, CHRISTOPHER NEWMAN (1816—19oz)
• HALL, EDWARD (c. 1498-1547)
• HALL, FITZEDWARD (1825-1901)
• HALL, ISAAC HOLLISTER (1837-1896)
• HALL, JAMES (1793–1868)
• HALL, JAMES (1811–1898)
• HALL, JOSEPH (1574-1656)
• HALL, MARSHALL (1790-1857)
• HALL, ROBERT (1764-1831)
• HALL, SAMUEL CARTER (5800-5889)
• HALL, SIR JAMES (1761-1832)
• HALL, WILLIAM EDWARD (1835-1894)

Hall and E . F . See also:

• SMITH
• SMITH, ADAM (1723–1790)
• SMITH, ALEXANDER (183o-1867)
• SMITH, ANDREW JACKSON (1815-1897)
• SMITH, CHARLES EMORY (1842–1908)
• SMITH, CHARLES FERGUSON (1807–1862)
• SMITH, CHARLOTTE (1749-1806)
• SMITH, COLVIN (1795—1875)
• SMITH, EDMUND KIRBY (1824-1893)
• SMITH, G
• SMITH, GEORGE (1789-1846)
• SMITH, GEORGE (184o-1876)
• SMITH, GEORGE ADAM (1856- )
• SMITH, GERRIT (1797–1874)
• SMITH, GOLDWIN (1823-191o)
• SMITH, HENRY BOYNTON (1815-1877)
• SMITH, HENRY JOHN STEPHEN (1826-1883)
• SMITH, HENRY PRESERVED (1847– )
• SMITH, JAMES (1775–1839)
• SMITH, JOHN (1579-1631)
• SMITH, JOHN RAPHAEL (1752–1812)
• SMITH, JOSEPH, JR
• SMITH, MORGAN LEWIS (1822–1874)
• SMITH, RICHARD BAIRD (1818-1861)
• SMITH, ROBERT (1689-1768)
• SMITH, SIR HENRY GEORGE WAKELYN
• SMITH, SIR THOMAS (1513-1577)
• SMITH, SIR WILLIAM (1813-1893)
• SMITH, SIR WILLIAM SIDNEY (1764-1840)
• SMITH, SYDNEY (1771-1845)
• SMITH, THOMAS SOUTHWOOD (1788-1861)
• SMITH, WILLIAM (1769-1839)
• SMITH, WILLIAM (c. 1730-1819)
• SMITH, WILLIAM (fl. 1596)
• SMITH, WILLIAM FARRAR (1824—1903)
• SMITH, WILLIAM HENRY (1808—1872)
• SMITH, WILLIAM HENRY (1825—1891)
• SMITH, WILLIAM ROBERTSON (1846-'894)

Smith, Proc . Amer . Philos . See also:

• SOC

Soc . 1905, 44, p . 177) . The See also:

• METAL
• METAL (through Fr. from Lat. metallum, mine, quarry, adapted from Gr. µATaXAov, in the same sense, probably connected with ,ueraAAdv, to search after, explore, µeTa, after, aAAos, other)

metal was first obtained by C .

W . Blomstrand (Journ. prak . Chem.1866, 97, p . 37) by reducing the chloride with See also:

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

hydrogen; it has more recently been prepared by H . See also:

• MOISSAN, HENRI (1852-1907)

Moissan by reducing the See also:

• OXIDE

oxide with See also:

• CARBON (symbol C, atomic weight 12)

carbon in the electric See also:

• FURNACE

furnace (the product obtained always contains from 2-3 % of combined carbon), and by H . See also:

• GOLDSCHMIDT, HERMANN (1802-1866)

Goldschmidt and C . Vautin (Journ . Soc . Chem . See also:

• INDUSTRY (Lat. industria, from indu-, a form of the pre, position in, and either stare, to stand, or struere, to pile up)

Industry, 1898, 19, p . 543) by reducing the oxide with See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium See also:

• POWDER (through O. Fr. puldre, modern poudre, from Lat. pulvis, pulveris, dust)

powder . As obtained by the reduction of the chloride, it is a See also:

• STEEL, FLORA ANNIE (1847– )

steel See also:

• GREY, CHARLES GREY, 2ND EARL (1764-1845)
• GREY, HENRY GREY, 3RD EARL (1802-1894)
• GREY, LADY JANE (1537-1554)
• GREY, SIR EDWARD
• GREY, SIR GEORGE (1812–1898)

grey powder of specific gravity 7.06 .

It See also:

• BURNS, JOHN (1858– )
• BURNS, ROBERT (1759-1796)
• BURNS, SIR GEORGE

burns on See also:

• HEATING

heating in See also:

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

air; and is scarcely attacked by hydrochloric or nitric acids, or by aqua regia; it is soluble in warm concentrated sulphuric acid . Columbium hydride, CbH, is obtained as a greyish metallic powder, when the double fluoride, CbF5, 2 KF, is reduced with See also:

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

sodium . It burns when heated in air, and is soluble in warm concentrated sulphuric acid . Three oxides of columbium are certainly known, namely the dioxide, Cb202, the tetroxide, Cb204, and the pentoxide, Cb205, whilst a See also:

• FOURTH

fourth oxide, columbium trioxide, Cb203, has been described by E . F . Smith and P . See also:

• MAAS, JOSEPH (1847-1886)

Maas (Zeit. f. anorg . Chem . 1894, 7, p . 97) . Columbium dioxide, Cb2O2, is formed when dry potassium columbium oxyfluoride is reduced by sodium (H . See also:

• ROSE
• ROSE (Rosa)
• ROSE, GEORGE (1744-1818)
• ROSE, HUGH JAMES (1795—1838)
• ROSE, WILLIAM STEWART (1775-1843)

Rose, Fogg .

Ann . 1858, 104, p . 312) . It burns readily in air, and is converted into the pentoxide when fused with acid potassium sulphate . Columbium Crystal of Columbite . ttroxide, Cb204, is obtained as a See also:

• BLACK
• BLACK, ADAM (1784-1874)
• BLACK, JEREMIAH SULLIVAN (1810–1883)
• BLACK, WILLIAM (1841-1898)

black powder when the pentoxide is heated to a high temperature in a current of hydrogen . It is unattacked by acids . Columbium pentoxide (columbic acid), Cb205, is obtained from columbite, after the removal of tantalum (see above) . The See also:

• MOTHER

mother liquors are concentrated, and the double See also:

• SALT (a common Teutonic word, cf. Dutch zout, Ger. Salz, Scand. salt; cognate with Gr. &Xs, Lat. sal)
• SALT, SIR TITUS, BART

salt of See also:

• COMPOSITION
• COMPOSITION (Lat. compositio, from componere, to put together)

composition 2KF•CbOF3 H20, which separates, is decomposed by sulphuric acid, or by continued boiling with water (C . Marignac; see also G . Kruss and L . F .

Nilson, Ber . 1887, 20. p . 1676) . It is a See also:

• WHITE
• WHITE, ANDREW DICKSON (1832– )
• WHITE, GILBERT (1720–1793)
• WHITE, HENRY KIRKE (1785-1806)
• WHITE, HUGH LAWSON (1773-1840)
• WHITE, JOSEPH BLANCO (1775-1841)
• WHITE, RICHARD GRANT (1822-1885)
• WHITE, ROBERT (1645-1704)
• WHITE, SIR GEORGE STUART (1835– )
• WHITE, SIR THOMAS (1492-1567)
• WHITE, SIR WILLIAM ARTHUR (1824--1891)
• WHITE, SIR WILLIAM HENRY (1845– )
• WHITE, THOMAS (1628-1698)
• WHITE, THOMAS (c. 1550-1624)

white amorphous infusible powder, which when strongly heated in sulphuretted hydrogen, yields an oxysulphide . Several hydrated forms are known, yielding salts known as columbates . A percolumbic acid, HCbO4•nH2O, has been prepared by P . Melikoff and L . Pissarjewsky (Zeit. f. anorg . Chem . 1899, 20, p . 341), as a yellow amorphous powder by the See also:

• ACTION

action of dilute sulphuric acid on the potassium salt, which is formed when columbic acid is fused in a See also:

• SILVER

silver crucible with eight times its See also:

• WEIGHT

weight of See also:

• CAUSTIC (Gr. rcavvraubs, burning)

caustic potash (loc. cit.) . Salts of the acid H3CbO, have been described by C .

W . Balke and E . F . Smith (Jour . Amer . Chem . Soc . 1908, 30, p . 1637) . Columbium trichloride, CbCl3, is obtained in needles or crystalline crusts, when the vapour of the pentachloride is slowly passed through a red-hot See also:

• TUBE (Lat. tuba)

tube . When heated in a current of carbon dioxide it forms the oxychloride CbOCI3, and carbon monoxide . Columbium pentachloride, CbC15, is obtained in yellow needles when a mixture of the pentoxide and See also:

• SUGAR

sugar See also:

• CHARCOAL

charcoal is heated in a current of air-See also:

• FREE

free See also:

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

chlorine .

It melts at 194° C . (H . Deville) and boils at 240.5° C . It is decomposed by water, and dissolves in hydrochloric acid . Columbium oxychloride, CbOCl3, is formed when carbon tetrachloride, and columbic acid are heated together at 440° C.: 3CC14+Cb205= 2CbOCl3+300012,and also by distilling the pentachloride,in a current of carbon dioxide, over ignited columbic acid . It forms a white silky mass which volatilizes at about 400° C . It deliquesces in moist air, and is decomposed violently by water . Columbium pentafluoride, CbF,, is obtained when the pentoxide is dissolved in hydrofluoric acid . It is only known in See also:

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

solution; evaporation of the solution yields the pentoxide . The oxyfluoride, CbOF3, results when a mixture of the pentoxide and fluorspar is heated in a current of hydrochloric acid . It forms many double salts with other metallic fluorides . Columbium oxysulphide, CbOS3, is obtained as a dark See also:

• BRONZE

bronze coloured powder when the pentoxide is heated to a white 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 in a current of carbon bisulphide vapour; or by gently heating the oxychloride in a current of sulphuretted hydrogen .

It burns when heated in air, forming the. pentoxide and See also:

• SULPHUR

sulphur dioxide . Columbium nitride, Cb3N5 (?), is formed when dry See also:

• AMMONIA (NH3)

ammonia See also:

• GAS

gas is passed into an ethereal solution of the chloride . A heavy white precipitate, consisting of ammonium chloride and columbium nitride, is thrown down, and the ammonium chloride is removed by washing it out with hot water, when the columbium nitride remains as an amorphous residue (Hall and Smith, loc. cit.) . Potassium fluoxy percolumbate, K2Cb02F5.H20, is prepared by dissolving potassium columbium oxyfluoride in a 3 % solution of hydrogen peroxide . The solution turns yellow in See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour, and, when saturated, deposits a pasty mass of crystals . The salt separates from solutions containing hydrofluoric acid in large plates, which are greenish yellow in colour . The atomic weight was determined by C . Marignac (Ann. chim. et phys . 1866 (4), 8, p . 16) to be 94 from the See also:

• ANALYSIS (Gr. avci and Meta, to break up into parts)

analysis of potassium columbium oxyfluoride, and the same value has been obtained by T . W . See also:

• RICHARDS, ALFRED BATE (182o-1876)
• RICHARDS, HENRY BRINLEY (1819-1865)
• RICHARDS, WILLIAM TROST (1833-1905)

Richards (Journ .

Amer . Chem . Soc . 1898, 20, p . 543) .