from See also:

• LAT

Lat. natrium; atomic See also:

• WEIGHT

weight 23.00 See also:

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

SODIUM [See also:

• SYMBOL (Gr. o-uµ(3oXov, a sign)

symbol Na (0=16)]  , a chemical See also:

• ELEMENT (Lat. elementum)

element belonging to the See also:

• GROUP

group of See also:

• ALKALI

alkali metals . It is abundantly and widely diffused in nature, but always in See also:

• COMBINATION (Lat. combinare, to combine)

combination . See also:

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

Sodium chloride, or See also:

• COMMON

common 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 (q.v.), is exceedingly common, being the See also:

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

chief salt See also:

• PRESENT

present in See also:

• SEA (in O. Eng. sae, a common Teutonic word; cf. Ger. See, Dutch Zee, &c.; the ultimate source is uncertain)
• SEA, COMMAND OF THE

sea-See also:

• WATER

water, besides occurring in extensive stratified deposits . Sodium See also:

• CARBONATES

carbonates are also widely dispersed in nature, forming constituents of many See also:

• MINERAL

mineral See also:

• WATERS, TERRITORIAL

waters, and occurring as See also:

• PRINCIPAL

principal saline components in See also:

• PATRON

patron or trona lakes, as efflorescences in See also:

• LOWER

Lower See also:

• EGYPT

Egypt, See also:

• PERSIA

Persia and See also:

• CHINA

China, and as urao in See also:

• MEXICO
• MEXICO (Span. Mejico, or Mexico,)
• MEXICO, FEDERAL DISTRICT OF
• MEXICO, GULF OF

Mexico, See also:

• COLOMBIA

Colombia and See also:

• VENEZUELA

Venezuela . The solid crusts found at the bottom of the salt lakes of the Araxes See also:

• PLAIN (O. Fr. plain, from Lat. plenum)

plain in See also:

• ARMENIA (old Persian Armina, Armenian Hayasdan, or Hayq)

Armenia contain about 16% of carbonate and 8o of sulphate . In Colombia there occurs a 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 salt, Na2COa• CaCOa•5HQO, known as See also:

• GAY, JOHN (1685-1732)
• GAY, MARIE FRANCOISE SOPHIE (1776-1852)
• GAY, WALTER (1856– )

gay-lussite . In See also:

• WYOMING

Wyoming, See also:

• CALIFORNIA
• CALIFORNIA, LOWER (Baja California)
• CALIFORNIA, UNIVERSITY OF

California and See also:

• NEVADA
• NEVADA (a Spanish word meaning " snow-clad " or " snowy land," originally applied to a snow-capped mountain range on the Pacific slope)

Nevada enormous deposits of carbonates, mixed in some cases with sulphate and with chloride, occur . About Szegedin in See also:

• HUNGARY
• HUNGARY (Hungarian Magyarorszdg)

Hungary and all over the vast pusztas (See also:

• STEPPES

steppes) between the See also:

• THEISS (Hungarian, Tisza; Lat., Tisia or Tissus)

Theiss and the See also:

• DANUBE (Ger. Donau, Hungarian Duna, Rumanian Dunarea, Lat. Danubius or Danuvius, and in the lower part of its course Ister)

Danube, and from the Theiss up to and beyond Debreczin, the See also:

• SOIL

soil contains sodium carbonate, which frequently assumes the See also:

• FORM (Lat. forma)

form of crude alkaline crusts, called " szekso," and of small saline ponds . A purified specimen of such Debreczin soda was found to contain as much as 90 % of real carbonate, NaCO3, and 4 of common salt Natural sulphate occurs in an anhydrous See also:

• CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition as thenardite, NaeSOr, at See also:

• TARAPACA

Tarapaca, See also:

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

Chile, and in the See also:

• ROCK
• ROCK (O.Fr. rake, Sp. rota, Ital. rocca; possibly from a Lat. form rupica, from rupes, rock)
• ROCK, DANIEL (1799–187t)

rock-salt deposits at Espartinas near See also:

• ARANJUEZ (perhaps the ancient Ara Jovis)

Aranjuez, See also:

• SPAIN
• SPAIN (Espana)

Spain . Hydrated sulphates occur at several localities in the See also:

• PROVINCE
• PROVINCE (Lat. provincia; perhaps a contraction of providentia)

province of See also:

• MADRID

Madrid and in other provinces of Spain, and at Muhlingen in See also:

• AARGAU (Fr. Argovie)

Aargau, and copious deposits of glauberite, the double sulphate of sodium and See also:

• CALCIUM [symbol Ca, atomic weight 40.0 (o= x6)]

calcium, are met with in the salt-mines of Villarrubia in Spain, at See also:

• STASSFURT

Stassfurt, and in the province of Tarapaca, Chile, &c . A native nitrate of soda is obtained in See also:

• GREAT

great abundance in the See also:

• DISTRICT

district of See also:

• ATACAMA
• ATACAMA, DESERT OF

Atacama and the province of Tarapaca, and is imported into See also:

• EUROPE

Europe in enormous quantities as cubic See also:

• NITRE

nitre for the preparation of See also:

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

saltpetre . See also:

• CRYOLITE

Cryolite, a fluoride of See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium and sodium, is extensively See also:

• MINED

mined in See also:

• GREENLAND (Danish, &c., Gronland)

Greenland and elsewhere for See also:

• INDUSTRIAL

industrial purposes .

These form the principal natural See also:

• SOURCES

sources of sodium compounds—the chloride as rock salt and in sea-water being of such predominating importance as quite to outweigh all the others . But it is questionable whether, taken altogether, the See also:

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

mass of sodium they represent is as much as that disseminated throughout the rocky crust in the form of soda See also:

• FELSPAR, or FELDSPAR

felspar (i.e. as silicate of soda) and in other soda-containing rocks . From this source all soils contain small proportions of sodium in soluble forms, hence the ashes of See also:

• PLANTS

plants, although they preferably imbibe See also:

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

potassium salts, contain traces and sometimes notable quantities of sodium salts . Sodium salts also form essential ingredients in all See also:

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

animal juices . Although many sodium compounds have been known from very remote times, the element was not isolated until 1807, when See also:

• SIR

Sir H . See also:

• DAVY, SIR HUMPHRY

Davy obtained it by electrolysing See also:

• CAUSTIC (Gr. rcavvraubs, burning)

caustic soda . This method was followed by that proposed by Gay-Lussac and See also:

• THENARD, LOUIS JACQUES (1777-1857)

Thenard, who decomposed molten caustic soda with red-hot See also:

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

iron; and this in turn was succeeded by See also:

• BRUNNER, HENRY (184o– )

Brunner's See also:

• PROCESS

process of igniting sodium carbonate with See also:

• CHARCOAL

charcoal . Deville made many improvements, but the method remained wasteful and uneconomical, and in 1872 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 cost 4s. a See also:

• POUND
• POUND (2)—(a)

pound . In 1886, however, Castner replaced the carbonate by caustic soda, and materially cheapened the cost of See also:

• PRODUCTION (Lat. productionem, from producere, to pro-duce)

production; but this method was discarded for an electrolytic one, patented by Castner in 1890 . Electrolytic processes had, in fact, been considered since 1851, when See also:

• CHARLES
• CHARLES (1270-1325)
• CHARLES (1421-1461)
• CHARLES (1525-1574)
• CHARLES (c. 1319-1364)
• CHARLES (Fr. Charles; Span. Carlos; Ital. Carlo; Ger. Karl; derived from O.H.G. Charal,latinized as Carolus, meaning originally " man ": cf. Mod.Ger., Kerl," fellow," A.S. ceorl, Mod. Eng. " churl ")
• CHARLES (KARL EITEL ZEPHYRIN LUDWIG; in Rum. CAROL)
• CHARLES [KARL ALEXANDER] (1712-1780)
• CHARLES, ELIZABETH (1828-1896)
• CHARLES, JACQUES ALEXANDRE CESAR (1746-1823)
• CHARLES, THOMAS (1755-1814)

Charles See also:

• WATT, JAMES (1736-1819)

Watt patented his method for the production of sodium and potassium from fused chlorides . Among the difficulties here to be contended with are the destructive See also:

• ACTION

action of fused chlorides and of the reduced alkali metals upon most non-metallic sub-stances available for the containing See also:

• VESSEL (O. Fr. vaissel, from a rare Lat. vascellum, dim. of vas, vase, urn)

vessel and its See also:

• PARTITION

partition, and also of the anode See also:

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

chlorine upon metals; also the See also:

• LOW, SETH (1850- )
• LOW, WILL HICOK (1853- )

low fusing-point (95° C. for sodium, and 62° C. for potassium) and the low specific gravity of the metals, so that the separated metal floats as a fused layer upon the See also:

• TOP (cf. Dan. top, Ger. Topf, also meaning pot)

top of the melted salt . Again, pure sodium chloride melts at about 7750 C., while sodium boils at 877° C., so that the margin of safety is but small if loss by See also:

• VAPORIZATION

vaporization is to be prevented .

Borchers endeavoured to See also:

• CON

con-tend against the first difficulty by employing an iron See also:

• CATHODE

cathode vessel and- a chamotte (See also:

• FIRE (in O. Eng. f j'r; the word is common to West German languages, cf. Dutch vuur, Ger. Feuer; the pre-Teutonic form is seen in Sanskrit pu, pavaka, and Gr. irup; the ultimate origin is usually taken to be a root meaning to purify, cf. Lat. purus)

fire-See also:

• CLAY (from O. Eng. claeg, a word common in various forms to Teutonic languages, cf. Ger. Klei)
• CLAY, CASSIUS MARCELLUS (1810-1903)
• CLAY, CHARLES (1801–1893)
• CLAY, FREDERIC (1838–1889)
• CLAY, HENRY (1777–1852)

clay) anode chamber See also:

• UNITED

united by a specially constructed water-cooled See also:

• JOINT (through Fr. from Lat. junctum, jungere, to join)

joint . The other difficulty is to some extent met by using mixed chlorides (e.g. sodium, potassium and See also:

• STRONTIUM [Symbol Sr, atomic weight 87.62 (0=16)]

strontium chlorides for sodium extraction), as these melt at a lower temperature than the pure chloride . In Castner's process (as employed at See also:

• OLDBURY

Oldbury and See also:

• NIAGARA
• NIAGARA, FORT

Niagara Falls and in See also:

• GERMANY
• GERMANY (Ger. Deutschland)

Germany) fused caustic soda is electrolysed . The apparatus described in the patent See also:

• SPECIFICATION (from Med. Lat. specificatio, specificare, to enumerate or mention in detail)

specification is an iron See also:

• CYLINDER (Gr. KvAwSpos, from KvXivaety, to roll)

cylinder heated by See also:

• GAS

gas rings below, with a narrower cylinder beneath, through which passes upwards a stout iron cathode See also:

• ROD (O.E. rodd, probably related to Norw. rudda, stick, rodda, stake)
• ROD, EDOUARD (1857-1910)

rod cemented in See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place by caustic soda solidified in the narrower vessel . Iron anodes are suspended around the cathode, and between the two is a cylinder of iron See also:

• GAUZE

gauze at the bottom with a See also:

• SHEET

sheet-iron continuation above, the latter being provided with a movable See also:

• COVER (from the Fr. convert, from couvrir, to cover, Lat. cooperire)

cover . During See also:

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

electrolysis, See also:

• OXYGEN (symbol 0, atomic weight 16)

oxygen is evolved at the anode and escapes from the See also:

• OUTER

outer vessel, while the sodium deposited in globules on the cathode floats upwards into the iron cylinder, within which it accumulates, and from which it may be re-moved at intervals by means of a perforated iron ladle, the fused salt, but not the metal, being able to pass freely through the perforations . The sodium is then See also:

• CAST (from the verb meaning " to throw "; the word is Scand. in origin, cf. Dan. kaste, and Swed. kasta; " cast " in Middle Eng. took the place of the A.S. weor pan, cf. Ger. werf en)

cast into moulds . Sodium hydroxide has certain advantages compared with chloride, although it is more costly; its fusing-point is only 320° C., and no anode chlorine is produced, so that both containing vessel and anode may be of iron, and no porous partition is necessary . Metallic sodium possesses a silvery lustre, but on exposure to moist See also:

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

air the See also:

• SURFACE

surface is rapidly dulled by a layer of the hydroxide . It may be obtained crystallized in the quadratic See also:

• SYSTEM

system by melting in a sealed See also:

• TUBE (Lat. tuba)

tube containing See also:

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

hydrogen, allowed to cool partially, and then pouring off the still 'liquid portion by inverting the tube . The specific gravity is 0.9735 at 13.50(Baumhauer) . At See also:

• ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary temperatures the metal has the consistency of See also:

• WAX

wax and can be readily cut; on cooling it hardens .

On See also:

• HEATING

heating it melts at 95.6° (See also:

• BUNSEN, CHRISTIAN CHARLES JOSIAS, BARON VON (1791-186o,)
• BUNSEN, ROBERT WILHELM VON (1811-1899)

Bunsen) to a liquid resembling See also:

• MERCURY
• MERCURY (MERCU1uus)
• MERCURY (symbol Hg, atomic weight = 2oo)

mercury, and boils at 877.5° (See also:

• RUFF

Ruff and Johannsen, Ber., 1905, 38, p . 36or), yielding a vapour, colourless in thin layers but a See also:

• PECULIAR

peculiar See also:

• PURPLE

purple, with a greenish See also:

• FLUORESCENCE

fluorescence, when viewed through thick layers . (For the See also:

• OPTICS

optics of sodium vapour see R . W . See also:

• WOOD, ANTHONY A2 (1632-1695)
• WOOD, JOHN GEORGE (1827—1889)
• WOOD, MRS HENRY [ELLEN] (1814—1887)
• WOOD, SEARLES VALENTINE (1798—188o)

Wood, See also:

• PHYSICAL

Physical Optics.) According to A . Matthiessen, sodium ranks See also:

• FOURTH

fourth to See also:

• SILVER

silver, See also:

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

copper and See also:

• GOLD
• GOLD [symbol Au, atomic weight 195.7(H = 1),197.2(0 =16)]

gold as a conductor of See also:

• ELECTRICITY

electricity and 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, and according to Bunsen it is the most electropositive metal with the exception of See also:

• CAESIUM (symbol Cs, atomic weight 132.9)

caesium, See also:

• RUBIDIUM [symbol Rb, atomic weight 85.45 (0=16)]

rubidium and potassium . The metal is very reactive chemically . Exposed to moist air it rapidly oxidizes to the hydroxide; and it See also:

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

burns on heating in air with a yellow See also:

• FLAME (Lat. flamma; the root flag- appears in flagrare, to burn, blaze, and Gr. d, XEryew)

flame, yielding the monoxide and dioxide . A fragment thrown on the surface of water rapidly disengages hydrogen, which gas, however, does not inflame, as happens with potassium; but inflammation occurs if hot water be used, or if the metal be dropped on moist See also:

• FILTER (a word common in various forms to most European languages, adapted from the medieval Lat. fi-ltrum, felt, a material used as a filtering agent)

filter See also:

• PAPER
• PAPER (Fr. papier, from Lat. papyrus)

paper . Sodium also combines directly, sometimes very energetically, with most non-metallic elements . It also combines with dry See also:

• AMMONIA (NH3)

ammonia at 300-400° to form sodamide, NaNH2, 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 waxy mass when pure, which melts at 1550 . Heated in a current of See also:

• CARBON (symbol C, atomic weight 12)

carbon dioxide sodamide yields caustic soda and See also:

• CYANAMIDE

cyanamide, and with nitrous See also:

• OXIDE

oxide it gives sodium See also:

• AZOIMIDE

azoimide; it deflagrates with See also:

• LEAD
• LEAD (pronounced iced)

lead or silver nitrate and explodes with potassium chlorate .

Sodan3ide was introduced by Claisen (Ber., 1905, 38, p . 693) as a condensing See also:

• AGENT (from Lat. agere, to act)

agent in organic See also:

• CHEMISTRY
• CHEMISTRY (formerly "chymistry"; Gr. xvµela; for derivation see ALCHEMY)

chemistry, and has since been applied in many directions . Sodium is largely employed in the manufacture of cyanides and in reduction processes leading to the See also:

• ISOLATION

isolation of such elements as See also:

• MAGNESIUM [symbol Mg, atomic weight 24.32 (0 = 16)]

magnesium, See also:

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

silicon, See also:

• BORON (symbol B, atomic weight I I)

boron, aluminium (formerly), &c.; it also finds application in organic chemistry . With potassium it 'forms a liquid alloy resembling mercury, which has been employed in high temperature thermometers (See See also:

• THERMOMETRY (Gr. Bepµos, warm; µerpov, a measure)

THERMOMETRY) . Compounds . In its chemical combinations sodium is usually monovalent; its salts are generally soluble in water, the least soluble being the metantimonate . Sodium hydride, NaH, is a crystalline substance obtained directly from sodium and hydrogen, at, about 400° . It burns when heated in dry air, and ignites in moist air; it is decomposed by water, giving caustic soda and hydrogen . Dry carbon dioxide is decomposed by it, See also:

• FREE

free carbon being produced; moist carbon dioxide, on the other See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand, gives sodium formate . Several oxides are known . A suboxide, . Na30, appears to be formed as a 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 mass when a clean surface of the metal is exposed to air, or when pure air is passed through the metal just above its melting point (De Forcrand, Compt. rend., 1898, 12,7, pp .

344, 514)• The monoxide, Na2O, is obtained by heating the metal above 18o° in a limited amount of slightly moist oxygen (See also:

• HOLT, SIR JOHN (1642–1710)

Holt and See also:

• SIMS, GEORGE ROBERT (1847– )

Sims, fourn . Chem . See also:

• SOC

Soc., 1894, i . 442) ; It may also be prepared by heating the nitrate or nitrite with metallic sodium, free See also:

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

nitrogen being eliminated (See also:

• GERMAN
• GERMAN, DUTCH AND SCANDINAVIAN

German patent, 142467, 1902) . It forms a grey mass, which melts at a red heat and violently combines with water to give the hydroxide . The hydroxide or caustic soda, NaOH, is usually manufactured from the carbonate or by electrolysis of salt See also:

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

solution (see ALKALI MANUFACTURE) . When anhydrous it is a colourless opaque solid which melts at 310°, and decomposes at about 1 too° . It is very soluble in water, yielding a strongly alkaline solution; it also dissolves in See also:

• ALCOHOL

alcohol . It absorbs moisture and carbon dioxide from the See also:

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

atmosphere . Several hydrates are known: 2NaOH•7H20 is obtained as large See also:

• MONOCLINIC

monoclinic crystals by cooling a solution of specific gravity 1365 to -8°; See also:

• PICKERING
• PICKERING, EDWARD CHARLES (1846- )
• PICKERING, TIMOTHY (174 1829)

Pickering (Journ . Chem . Soc., 1893, 65, p .

890) obtained NaOH•See also:

• H2O (combined)

H2O from hot concentrated solutions and NaOH•2H2O from a solution of the hydroxide in 96 8 % alcohol . (See also De Forcrand, Compt. rend., 1901, 1331 p . 223.) Sodium dioxide, Na202, is formed when the metal is heated in an excess of air or oxygen . In practice the metal is placed on aluminium trays traversing an iron tube heated to 3000, through which a current of air, freed from moisture and carbon dioxide, is passed; the process is made continuous, and the product contains about 93 % Na2O2 . Wt.en pure, sodium dioxide has a faint yellowish tinge, but on exposure it whitens (W . R . 13ousfield and T . M . Lowry, Phil . Trans., 1905, A . 204, p: 253) . When dissolved in water it yields some NaOH and H202; on cr'stallizing a See also:

• COLD (in O. Eng. cald and ceald, a word coming ultimately from a root cognate with the Lat. gelu, gelidus, and common in the Teutonic languages, which usually have two distinct forms for the substantive and the adjective, cf. Ger. Kolte, kalt, Dutch koude

cold solution Na202 81120 separates as large See also:

• TABULAR

tabular hexagonal crystals, which on drying over sulphuric See also:

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

acid give Na202 2H20, the former is also obtained by precipitating a mixture of caustic soda and hydrogen peroxide solutions with alcohol .

Acids yield a sodium salt and free oxygen or hydrogen peroxide; with carbon dioxide it gives sodium carbonate and free oxygen; carbon monoxide gives the carbonate; whilst nitrous and nitric oxides give the nitrate . A solution in hydrochloric acid, consisting of the chloride and hydrogen peroxide, is used for 'See also:

• BLEACHING

bleaching See also:

• STRAW

straw under the name of soda-bleach; with calcium or magnesium chlorides this solution gives a solid product which, when dissolved in water, is used for the same purpose (Castner, Journ . Soc . Chem . Ind., 1893, p . 603) . Sodium dioxide is chiefly employed as an oxidizing agent, being used in mineral See also:

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

analysis and in various organic preparations; it readily burns paper, wood, &c., but does not evolve oxygen unless heated to a high temperature . Sodyl hydroxide, NaHOs, exists in two forms: one, Na•O.OH, obtained from hydrogen peroxide and sodium ethylate; the other, O:Na.OH, from See also:

• ABSOLUTE (Lat. absolvere, to loose, set free)

absolute alcohol and sodium peroxide at o° . They are strong oxidizing agents and yield alkaline solutions which readily evolve oxygen on heating . Sodium trioxide, Na20s, is said to be formed from an excess of oxygen and a solution of sodammonium in liquid ammonia . Water decomposes it, giving oxygen and the dioxide . Generally speaking, sodium salts closely resemble the corresponding potassium salts, and their methods of preparation are usually the same .

For sodium salts not mentioned below reference should be made to articles wherein the acid is treated, unless otherwise indicated . Sodium combines directly with the See also:

• HALOGENS

halogens to form salts which are soluble in water and crystallize in the cubic system . The fluoride, NaF, is sparingly soluble in water (I See also:

• PART

part in 25) . For the chloride see SALT . The bromide and iodide crystallize from hot solutions in anhydrous cubes; from solutions at ordinary temperatures in monoclinic prisms with 2H20; and at low temperatures with 5H20 . According to M . Loeb (Journ . Amer . Chem . Soc., 1905, 27, p . I019) the iodide differs from the other haloid salts in separating from solution in See also:

• ALCOHOLS
• ALCOHOLS, ALDEHYDES AND
• ALCOHOLS, BENZYL ALCOHOL, BUTYL ALCOHOLS, METHYL ALCOHOL

alcohols with " alcohol of See also:

• CRYSTALLIZATION

crystallization." Sodium sulphide, Na2S, obtained by saturating a caustic soda solution with sulphuretted hydrogen and adding an See also:

• EQUIVALENT

equivalent of alkali, is employed in the manufacture of soluble soda See also:

• GLASS
• GLASS (O.E. glees, cf. Ger. Glas, perhaps derived from an old Teutonic root gla-, a variant of glo-, having the general sense of shining, cf. " glare," " glow ")
• GLASS, STAINED

glass . Sodium sulphite, NasSOs, which is employed as an antichlor, is prepared (with 7H20) by saturating a solution of sodium carbonate with See also:

• SULPHUR

sulphur dioxide, adding another equivalent of carbonate and crystallizing .

The anhydrous salt may be prepared by heating a saturated solution of the hydrated salt . H . See also:

• HARTLEY, DAVID (1705–1757)
• HARTLEY, JONATHAN SCOTT (1845– )
• HARTLEY, SIR CHARLES AUGUSTUS (1825– )

Hartley and W . H . See also:

• BARRETT, LAWRENCE (1838-1891)
• BARRETT, LUCAS (1837-1862)

Barrett (Journ . Chem . Soc., 1909, 95, p . 1184) failed to obtain a decahydrate which had been previously described . The acid sulphite, NaHSO3, obtained by saturating a cold solution of the carbonate with sulphur dioxide and precipitating by alcohol, is employed for sterilizing See also:

• BEER

beer casks . Sodium sulphate, Na1SO•, known in the hydrated condition (with ioH2O) as See also:

• GLAUBER, JOHANN RUDOLF (1604-1668)

Glauber's salt, is manufactured in large quantities for See also:

• CONVERSION (Lat. conversio, from convertere, to turn or ,change)

conversion into the carbonate or soda (see ALKALI MANUFACTURE) . It has See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long been doubted whether sodium yielded an See also:

• ALUM

alum; this was settled by N . I .

Surgunoff in 1909 (Abst . Journ . Chem . Soc. ii . IooI), who obtained cubic crystals from a supersaturated solution of sodium and aluminium sulphates below 20°, higher temperatures giving monoclinic crystals . The acid sulphate, NaHSO4, also known as bisulphate of soda, is obtained as large See also:

• ASYMMETRIC

asymmetric prisms by crystallizing a solution of equivalent quantities of the normal sulphate and sulphuric acid above 5o° . The acid salts Na3H (SO4)s and NaiH(SO4)s•H20 are obtained from the normal sulphate and sulphuric acid (J . D'Ans; Ber., 1906, 39, p . 1534) . The manufacture of sodium carbonate, commonly called soda, is treated under ALKALI MANUFACTURE . The anhydrous salt is a colourless See also:

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

powder or porous mass, having an alkaline See also:

• TASTE (from Lat. taxare, to touch sharply; tangere, to touch)

taste and reaction . It melts at too8 .

On solution in water, heat is evolved and hydrates formed . Common washing soda or soda-crystals is the decahydrate, Na2CO3'I0H2O, which appears as large clear monoclinic crystals . On exposure, it loses water and gives, the monohydrate, Na2CO2.H2O, a white powder sold as " crystal carbonate "; this substance, which is also formed on heating the decahydrate to 34°, crystallizes in the rhombic system . Both these hydrates occur in the mineral See also:

• KINGDOM

kingdom, the former as natron and the latter as thermonatrite . The heptahydrate, Na2CO3.7H20, is obtained by crystallizing a warm saturated solution in a vacuum; it appears to be dimorphous . The acid carbonate or bicarbonate of soda, NaHCO3, is produced in the ammonia-soda process for alkali manufacture . Another acid carbonate, Na2COs 2NaHCO3.3Hs0, is the mineral trona or urao . We may here See also:

• NOTICE

notice the " percarbonates " obtained by Wolffenstein and Peltner (Ber., 1908, 41, pppp 275, 280) on acting with gaseous or solid carbon dioxide on Na202, Na20s and NaHO2 at low temperatures; the same authors obtained a perborate by adding sodium metaborate solution to a 50 % solution of sodium peroxide previously saturated with carbon dioxide . For sodium nitrite see NITROGEN; for sodium nitrate see SALTPETRE; for the See also:

• CYANIDE

cyanide see PRUSSIC ACID; and for the borate see See also:

• BORAX (sodium pyroborate or sodium biborate)

BORAX . Of the sodium silicates the most important is the mixture known as soluble soda glass formed by calcining a mixture of white See also:

• SAND
• SAND, GEORGE (1804-1876)

sand, soda-ash and charcoal, or by dissolving See also:

• SILICA

silica in hot caustic soda under pressure . It is a colourless transparent glass mass, which dissolves in boiling water to form a thick liquid . It is employed in certain See also:

• PRINTING (from Lat. imprimere, O. Fr. empreindre)

printing processes, as a See also:

• CEMENT (from Lat. caementum, rough pieces of stone, a shortened form of caedimentum, from caedere, to cut)

cement for artificial See also:

• STONE
• STONE (0. Eng. shin; the word is common to Teutonic languages, cf. Ger. Stein, Du. steen, Dan. and Swed. sten; the root is also seen in Gr. aria, pebble)
• STONE, CHARLES POMEROY (1824-1887)
• STONE, EDWARD JAMES (1831-1897)
• STONE, FRANK (1800-1859)
• STONE, GEORGE (1708—1764)
• STONE, LUCY [BLACKWELL] (1818-1893)
• STONE, MARCUS (184o— )
• STONE, NICHOLAS (1586-1647)

stone and for mending glass, See also:

• PORCELAIN

porcelain, &c., and also for making the so-called silicited soaps (see See also:

• SOAP

SOAP) .

GOMORRAH Sodium is most distinctly recognized by the yellow coloration which volatile salts impart to a Bunsen flame, or, better, by its emission spectrum which has a See also:

• LINE

line (double), the See also:

• FRAUNHOFER, JOSEPH VON (1787-1826)

Fraunhofer D, line, in the yellow (the See also:

• WAVE

wave-lengths are 5896 and 5890) . The 'atomic See also:

• WEIGHT

weight was determined by See also:

• STAS, JEAN SERVAIS (1813–1891)

Stas to be 22.87 (H = I) ; T . W . See also:

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

Richards and R . C . See also:

• WELLS
• WELLS, CHARLES JEREMIAH (1798?–1879)
• WELLS, DAVID AMES (1828—1898)
• WELLS, HERBERT GEORGE (1866— )
• WELLS, SIR THOMAS SPENCER, 1ST BART

Wells (Journ . Amer . Chem . Soc., 1905, 27, p . 459) obtained, the value 23.006 (0 =16) . See also:

• MEDICINE

Medicine . See also:

• PHARMACOLOGY

Pharmacology.—The metal sodium is not used in medicine, but many of ,its salts are employed .

Besides liquor sodii ethylatis the following salts and preparations are used in the See also:

• BRITISH

British See also:

• PHARMACOPOEIA (lit. the art of the OapµaK07robbs, or drug-compounder)

Pharmacopoeia . (I) Sodii tarbonis, known as washing soda; this carbonate on heating yields sodii carbonis exsiccaius and sodii bicarbonas; from the, latter is made trochiscus sodii bicarbonatis . (2) Sodii phosphas . From sodium phosphate are made sodii phosphas effervescens and sodii by ophosphis (ssee See also:

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

PHOSPHORUS) . (3) Sodii sulphas (Glauber's salt), with its sub-preparation sodii sulphas effervescens . (4) Soda tartarata (Rochelle salt), a tartrate of sodium and potassium, from which is made pulvis sodae tartaratae effervescens, known as Seidlitz powder . (5) Sodii cilro-tartras effervescens, a mixture of See also:

• SUGAR

sugar, sodium bicarbonate, citric and tartaric acids . (6) Sodii chloridum, common salt . (7) Sodii sulphas . For sodii bromidum, iodidum and salicylatum see See also:

• BROMINE (symbol Br, atomic weight 79-96)

BROMINE, See also:

• IODINE (symbol I, atomic weight '26.92)

IODINE and SALICYLIC ACID respectively . For sodii arsenas and cacodylale see See also:

• ARSENIC (symbol As, atomic weight 75.0)

ARSENIC . Sapo durus (hard soap) is a See also:

• COMPOUND
• COMPOUND (from Lat. componere, to combine or put together)

compound of sodium with See also:

• OLIVE (Olea europaea)

olive oil, and See also:

• SAGO

sago animalis (curd soap) is chiefly sodium stearate .

See also:

• TOXICOLOGY

Toxicology.—Poisoning by caustic soda is rare, but occasionally it takes place by swallowing soap lees (sodium carbonate), which may contain some impurities of caustic soda . The symptoms and treatment are the same as described under POTASSIUM . The salts of sodium resemble potassium in their action on the alimentary See also:

• TRACT (from Lat. tractare, to treat of a matter, through Provencal tractat and Ital. trattato)

tract, but they are much more slowly absorbed, and much less diffusible; therefore considerable amounts may reach the small See also:

• INTESTINE (Lat. intestinus, internal, usually in neuter plural intestina. from intus, within)

intestine and there See also:

• ACT (Lat. actus, actum)

act as saline purgatives . They are slowly absorbed into the See also:

• BLOOD

blood, and are a natural constituent of the blood plasma, which derives them from the See also:

• FOOD
• FOOD (like the verb " to feed," from a Teutonic root, whence O. Eng. foda; cf. " fodder "; connected with Gr. lrareicOae, to feed)

food . Sodium is excreted by all the mucous surfaces and by the See also:

• LIVER (O. Eng. lifer; cf. cognate forms, Dutch lever, Ger. Leber, Swed. lefver, &c.; the O. H. Ger. forms are libara, lipora, &c.; the Teut. word has been connected with Gr. i'prap and Lat. jecur)

liver and kidneys . On the latter they act as diuretics, but less powerfully than potassium, increasing the flow of water and the output of See also:

• UREA, or CARBAMIDE, CO(NH2)2

urea and rendering the urine less acid . They are said to diminish the secretion of the bronchial mucous membrane . See also:

• THERAPEUTICS (Gr. BepaaeuTLKIi, Sc. TEXVrt, from Beparebsty, to serve)

Therapeutics: See also:

• EXTERNAL

External Use.—The liquor sodii ethylatis is a powerful caustic and is used to destroy small naevi and warts . A lotion of sodium bicarbonate is useful to allay itching . Solutions of sodium sulphite are used as mild antiparasitics . See also:

• INTERNAL

Internal use.—Sodium chloride 'is occasionally used in warm water as an emetic, and injections of it into the rectum as a treatment for See also:

• THREAD (0. Eng. praed, literally, that which is twisted, prawan, to twist, to throw, cf. " throwster," a silk-winder, Ger. drehen, to twist, turn, Du. draad, Ger. Draht, thread, wire)

thread See also:

• WORMS

worms . A o.9% solution forms what is termed normal saline solution, which, is frequently injected into the tissues in cases of collapse, See also:

• HAEMORRHAGE (Gr. atµa, blood, and prryvvvac, to burst)

haemorrhage and See also:

• DIARRHOEA (from Gr. &Q, through, pfw, flow)

diarrhoea .

It forms a valuable treatment in diabetic See also:

• COMA (Gr. K(.7)

coma and eclampsia, acting by diluting the toxins in the blood . From this has See also:

• DEVELOPED

developed the intramuscular injection of diluted sea-water in the treatment of gastro-See also:

• ENTERITIS (Gr. Evrepov, intestine)

enteritis, See also:

• ANAEMIA (from Gr. ay-, privative, and aiµa, blood)

anaemia and' various skin affections . Sodium chloride is an important constituent of the waters of Homburg, See also:

• WIESBADEN

Wiesbaden, See also:

• NAUHEIM

Nauheim and See also:

• KISSINGEN

Kissingen . Sodium bicarbonate is one of our most useful gastric sedatives and antacids, relieving See also:

• PAIN (from Lat. poena, Gr. robin, penalty, that which must be paid: O. Fr. peine)
• PAIN, BARRY (1867– )

pain in hyperchloridia . It is the constituent of most stomachic mixtures . Effervescent soda water is a mild gastric sedative . Sodium phosphate and sulphate are cholagogue purgatives and are used in the treatment of gallstones . The sulphate is the chief constituent of See also:

• MARIENBAD

Marienbad and See also:

• CARLSBAD

Carlsbad waters . Large doses of these salts are used to remove fluid in See also:

• DROPSY (contracted from the old word hydropisy, derived from the Gr. 154w¢; i Swp, water, and appearance)

dropsy . Soda tartarate is purgative and diuretic, as is the citro-tartarate . These purgative sodium salts are most useful in the treatment of chronic See also:

• CONSTIPATION (from Lat. constipare, to press closely together, whence also the adjective " costive ")

constipation, and of the constipation associated with See also:

• GOUT

gout and hepatic See also:

• DYSPEPSIA (from the Gr. prefix Sur-, hard, ill, and 'irirreiv, to digest)

dyspepsia . They should be dissolved in warm water and taken in the See also:

• MORNING

morning, See also:

• FASTING (from " fast," derived from old Teutonic fastejan; synonyms being the Gr. vnorebety, late Lat. jejunare)

fasting .

In visceral gout and chronic catarrhal conditions of the See also:

• STOMACH (Gr. vrbsaxos from arbga, a mouth)

stomach a course of alkaline waters is distinctly beneficial . Sodium salts have not the depressant effect so marked in those of potassium .