| Identification | More | [Name]
Sodium | [CAS]
7440-23-5 | [Synonyms]
sodio
Sodium
NA 1421
Nametal
Natrium
sodium-23
COCKTAIL NA
sodium atom
SODIUM LUMP
SODIUM LUMPS
SODIUM METAL
Na 1000μg/mL
Sodium ingot
Sodium Metals
DIETARYSODIUM
NATRIUMMETALL
Metallic sodium
Sodium in water
Sodium (99.95%)
Sodium solution
SODIUM STANDARD
Sodium USP/EP/BP
sodium metallic
Sodium dispersion
Sodium, dry stick
SODIUM METAL 99.5%
SODIUM IC STANDARD
Sodium metal 250GM
Sodium metal 500GM
Sodium pieces, 99%
SODIUM AA STANDARD
SODIUM ICP STANDARD
SODIUM, POWDER, DRY
sodium(liquidalloy)
SODIUM, 3N5: 99.95%
SODIUM: 99.95%, 3N5
SODIUM REAGENT (ACS)
Sodium (Metals Basis)
Sodium pieces, GR 99%+
SodiumingotACSunderoil
SODIUM ICP/DCP STANDARD
SodiumNprescoredampoule
Sodium ACS reagent, dry
"Sodium Ingot, ampouled"
SODIUM STANDARD SOLUTION
Sodium ingot (min.99.8%)
Sodium solution 1000 ppm
SODIUMMETAL,INGOT,REAGENT
Sodium, Breakseal Ampoule
SODIUM INGOT: 99.8%, (ACS)
Sodium solution 10 000 ppm
Sodium, 99.5%, oiled sticks
Sodium Dispersion 40% in Oil
Sodium Metal (In Mineral Oil)
SODIUM, AAS STANDARD SOLUTION
Sodium(Metal)InLiquidParaffin
SODIUM, 40% DISPERSION IN OIL
Sodium, sticks, in mineral oil
Dupont sodium metal dispersion
SODIUM, LUMP, IN KEROSENE, 99%
Sodium,sticks,inmineraloil,99%
SODIUM SINGLE ELEMENT STANDARD
Avibactam Impurity 38 (Sodium)
Sodium,99.8%,under mineral oil
SODIUM METALLO-ORGANIC STANDARD
SODIUM PLASMA EMISSION STANDARD
Sodium(Metal)InLiquidParaffinGr
THIOGLYCOLLATE MEDIUM USP 20X9ML
Sodium(99.95%)(breaksealampoule)
Sodium(99.95%)(prescoredampoule)
Sodium, under mineral oil, 99.8%
SODIUM, PLASMA STANDARD SOLUTION
SODIUM SINGLE COMPONENT STANDARD
Sodium, Breakseal Ampoule 99.95%
SODIUM AA SINGLE ELEMENT STANDARD
SODIUM ATOMIC ABSORPTION STANDARD
SODIUM, LARGE PIECES, IN KEROSENE
SodiumNbreaksealampouleunderargon
Sodium standard solution 1000 ppm
Sodium, ingot, 99.95% metals basis
Sodium AA Standard,1000 ppm in HNO3
SODIUM ATOMIC SPECTROSCOPY STANDARD
SODIUM, OIL BASED STANDARD SOLUTION
"Sodium Pieces, 3-12 mm, under oil"
SODIUM, CUBE, IN MINERAL OIL, 99.95%
BUFFERS PH 4,00(20°C) 7,00 (20°C)9,00
SODIUM, ORGANIC AAS STANDARD SOLUTION
SODIUM SINGLE ELEMENT PLASMA STANDARD
1-cyano-3,3,3-trifluoro-propen-2-olate
BUFFERS PH 4,00(20°C) 7,00 (20°C)10,00
3,5-diacetamido-2,4,6-triiodo-benzoate
SODIUM 25 WT. % DISPERSION IN TOLUENE
TODD HEWITT BROTH + ANTIBIOTIC 120X10ML
Sodium 99.95% trace metals basis, ingot
SODIUM STANDARD SOLUTION TRACEABLE TO SR
SODIUM ICP STANDARD TRACEABLE TO SRM FRO
SODIUM ROD DIAMETER 2.5 CM (PROTECTIVE L
SODIUM AA/ICP CALIBRATION/CHECK STANDARD
Sodium 25-35 wt % dispersion in paraffin
Sodium, Product meets ACS specifications
SODIUM, 40 WT. % DISPERSION IN NAPHTHEN&
SODIUM STICK DRY A.C.S. REAGENT &
SODIUM 30-35 WT. % DISPERSION IN PARAF&
Sodiumdispersiongraysuspensioninmineraloil
SODIUM, 25WT. % DISPERSION IN PARAFFIN WAX
Sodium, metal, extra pure, in vaseline oil
SODIUM ATOMIC ABSORPTION STANDARD SOLUTION
"Sodium Sticks, 2.5 cm diameter, under oil"
Sodium, AAS standard solution, Na 1000μg/mL
Sodium, plasma standard solution, Specpure?
SODIUM PLASMA EMISSION SPECTROSCOPY STANDARD
SODIUM, 30-35 WT. % DISPERSION IN PARAFFIN WAX
Sodium Oil based standard solution, Na 1000μg/g
Sodium, oiled sticks, wrapped in aluminium foil
Sodium, Oil based standard solution, Na 5000μg/g
SODIUM ATOMIC ABSORPTION SINGLE ELEMENT STANDARD
Sodium, Reference Standard Solution, 1000ppm ±1%
Standard solution for the determination of sodium
Sodium standard solution, 1 mg/ml Na in 0.5N HNO3
Sodium,99.8%,oiled sticks, wrapped in aluminium foil
SODIUM, STICK, DRY, A.C.S. REAGENT (UNDE R NITROGEN)
Sodium, oiled sticks, wrapped in aluminium foil, 99.8%
SODIUM DISPERSION, GRAY SUSPENSION: 40% IN MINERAL OIL
SODIUM, SPHERES, 3 TO 8MM, IN ODORLESS M INERAL SPIRITS
Sodium, AAS standard solution, Specpure(R), Na 1000μg/ml
Sodium, 30wt% dispersion in toluene, <0.1 mm particle size
SodiuM, oiled sticks, wrapped in aluMiniuM foil, 99.8% 1KG
SodiuM in kerosene, pieces (large), >=99.8% (sodiuM basis)
2-(2,4,5,7-tetrabromo-3-hydroxy-6-oxoxanthen-9-yl)benzoate
SD Super Fine(TM) (Sodium 25wt% dispersion in mineral oil)
Sodium, plasma standard solution, Specpure(R), Na 1000μg/ml
SodiuM cubes, contains Mineral oil, 99.9% trace Metals basis
SodiuM, oiled sticks, wrapped in aluMiniuM foil, 99.8% 100GR
Sodium, plasma standard solution, Specpure(R), Na 10,000μg/ml
Sodium, Oil based standard solution, Specpure(R), Na 5000μg/g
Sodium, Oil based standard solution, Specpure(R), Na 1000μg/g
SODIUM, REAGENT (ACS)SODIUM, REAGENT (ACS)SODIUM, REAGENT (ACS)
Sodium, Organic AAS standard solution, Specpure|r, Na 1000^mg/g
[7-(3-tert-butoxycarbonylamino-propyl)-2,7-diaza-spiro[4.4]non-2-yl]-acetate
4-[[4-[(2-chlorophenyl)-[4-[ethyl-[(4-sulfonatophenyl)methyl]azaniumylidene]cyclohexa-2,5-dien-1-ylidene]methyl]-N-ethylanilino]methyl]benzenesulfonate
4-[[4-[[4-(diethylamino)phenyl]-[4-[ethyl-[(4-sulfonatophenyl)methyl]azaniumylidene]cyclohexa-2,5-dien-1-ylidene]methyl]-N-ethylanilino]methyl]benzenesulfonate
3-[[4-[4-[[4-(4-ethoxyanilino)phenyl]-[4-[ethyl-[(3-sulfonatophenyl)methyl]azaniumylidene]cyclohexa-2,5-dien-1-ylidene]methyl]-N-ethylanilino]-N-ethylanilino]methyl]benzenesulfonate | [EINECS(EC#)]
231-132-9 | [Molecular Formula]
Na | [MDL Number]
MFCD00085307 | [Molecular Weight]
22.99 | [MOL File]
7440-23-5.mol |
| Chemical Properties | Back Directory | [Definition]
Metallic element, atomic number 11, group IA of
periodic table, aw 22.98977, valence = 1, no stable
isotopes but several radioactive forms, extremely
reactive.
| [Appearance]
Soft, silver-white solid oxidizing rapidly
in air; waxlike at room temperature, brittle at low
temperatures. Store in airtight containers or in naph-
tha or similar liquid that does not contain water or
free oxygen.
Decomposes water on contact, with evolution of
hydrogen to form sodium hydroxide; insoluble in
benzene, kerosene, and naphtha. Has excellent elec-
trical conductivity and high heat-absorbing capac-
ity.
| [Melting point ]
97.8 °C (lit.) | [Boiling point ]
883 °C (lit.) | [density ]
1.04 g/mL at 20 °C
| [vapor pressure ]
1 mm Hg ( 440 °C)
| [Fp ]
128 °F
| [storage temp. ]
water-free area | [solubility ]
H2O: soluble
| [form ]
pieces (large)
| [color ]
White to off-white | [Specific Gravity]
0.97 | [Stability:]
Reacts violently with water, liberating and possibly igniting hydrogen. Flammable solid. Incompatible with water, strong oxidizing agents. Do not store near oxidants. Store under oil, or dry inert gas. Air sensitive. | [Resistivity]
4.69 μΩ-cm, 20°C | [Water Solubility ]
REACTS | [Sensitive ]
Air & Moisture Sensitive | [Merck ]
14,8570 | [InChIKey]
MPMYQQHEHYDOCL-UHFFFAOYSA-N | [History]
Long
recognized in compounds, sodium was first isolated by Davy
in 1807 by electrolysis of caustic soda. Sodium is present in
fair abundance in the sun and stars. The D lines of sodium are
among the most prominent in the solar spectrum. Sodium is
the sixth most abundant element on earth, comprising about
2.6% of the Earth’s crust; it is the most abundant of the alkali
group of metals of which it is a member. The most common
compound is sodium chloride, but it occurs in many other
minerals, such as soda niter, cryolite, amphibole, zeolite, sodalite,
etc. It is a very reactive element and is never found free
in nature. It is now obtained commercially by the electrolysis
of absolutely dry fused sodium chloride. This method is
much cheaper than that of electrolyzing sodium hydroxide,
as was used several years ago. Sodium is a soft, bright, silvery
metal that floats on water, decomposing it with the evolution
of hydrogen and the formation of the hydroxide. It may
or may not ignite spontaneously on water, depending on the
amount of oxide and metal exposed to the water. It normally
does not ignite in air at temperatures below 115°C. Sodium
should be handled with respect, as it can be dangerous when
improperly handled. Metallic sodium is vital in the manufacture
of sodamide and esters, and in the preparation of organic compounds. The metal may be used to improve the structure
of certain alloys, to descale metal, to purify molten metals,
and as a heat transfer agent. An alloy of sodium with potassium,
NaK, is also an important heat transfer agent. Sodium
compounds are important to the paper, glass, soap, textile,
petroleum, chemical, and metal industries. Soap is generally
a sodium salt of certain fatty acids. The importance of common
salt to animal nutrition has been recognized since prehistoric
times. Among the many compounds that are of the
greatest industrial importance are common salt (NaCl), soda
ash (Na2CO3), baking soda (NaHCO3), caustic soda (NaOH),
Chile saltpeter (NaNO3), diand tri-sodium phosphates, sodium
thiosulfate (hypo, Na2S2O3 · 5H2O), and borax (Na2B4O7
· 10H2O). Seventeen isotopes of sodium are recognized.
Metallic sodium is priced at about $575/kg (99.95%). On a
volume basis, it is the cheapest of all metals. Sodium metal
should be handled with great care. It should be kept in an inert
atmosphere and contact with water and other substances with
which sodium reacts should be avoided. | [Uses]
This soft silvery metal occurring as chlorine in seawater was
first isolated as an element by Humphry Davy in 1807. Sodium
is one of the essential elements required by living organisms
and it is highly reactive oxidizing in air and reacting with
water. Sodium chloride was the first halide to be combined
with silver for photographic purposes. Many of the sodium
compounds were also used in gold toning baths. Some of them
are included here. | [CAS DataBase Reference]
7440-23-5(CAS DataBase Reference) | [NIST Chemistry Reference]
Sodium(7440-23-5) | [EPA Substance Registry System]
7440-23-5(EPA Substance) |
| Safety Data | Back Directory | [Hazard Codes ]
C,F,T | [Risk Statements ]
R34:Causes burns.
R14/15:Reacts violently with water, liberating extremely flammable gases .
R45:May cause cancer. | [Safety Statements ]
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S8:Keep container dry .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S43:In case of fire, use ... (indicate in the space the precise type of fire-fighting equipment. If water increases the risk add-Never use water) .
S53:Avoid exposure-obtain special instruction before use . | [RIDADR ]
UN 3264 8/PG 3
| [WGK Germany ]
1
| [RTECS ]
VY0686000
| [Autoignition Temperature]
>115 °C in air | [TSCA ]
Yes | [HazardClass ]
4.3 | [PackingGroup ]
I | [HS Code ]
31025000 | [Safety Profile]
Metahc sodtum reacts exothermally with the moisture of body or tissue surfaces, causing thermal and chemical burns. Sodium in elemental form is highly reactive. Sodium reacts violently with water to form sodium hydroxide. A very dangerous fire hazard when exposed to heat and moisture. Under the appropriate condttions, it can react violently with moisture, air, ALBr3, dcl3, AlF3, NH4 chlorocuprate, NH4NO3, SbBr3, SbCl3, SbI3, AsCl3, Ash, Bil3r3, BiCl3, BiI3, Biz03, BBr3, bromoazide, Con, CO + NH3, cCl4, Cl2, ClF3, CrCl4, Cr03, CoBr, CoCl, CuCl2, CuO，F(xiàn)eBrs, FeCL, FeBr2, FeCl2, FeI2, hydrazine hydrate, H202, H2S, HCl, HF, F2, 1,2dichloroethylene, dichloromethane, Brz, hydroxylamine, iodine, iodine monochloride, iodine pentafluoride, lead oxide, maleic anhydride, manganous chloride, mercuric bromide, mercuric chloride, mercuric fluoride, mercuric iodide, mercurous chloride, mercurous oxide, methyl chloride, molybdenum trioxide, monoammonium phosphate, nitric acid, nitrogen peroxide, nitrosyl fluoride, nitrous oxide, phosgene, phosphorus, phosphorus pentafluoride, phosphorus pentoxide, phosphorus tribromide, phosphorus trichloride, phosphoryl chloride, potassium oxides, potassium ozonide, potassium superoxide, selenium, silicon tetrachloride, silver bromide, silver chloride, silver fluoride, silver iodide, sodium peroxide, stannic chloride, stannic iodide with sulfur, stannic oxide, stannous chloride, sulfur, sulfur dibromide, sulfur dichloride, sulfur dioxide, sulfuric acid, tellurium, tetrachloroethane, thallous bromide, thiophosphoryl bromide, trichlorethylene, vanadium pentachloride, vanadyl chloride, zinc bromide, any oxidizing material. Decomposes moisture to evolve hydrogen and heat. Reacts exothermally with halogens, acids, and halogenated hydrocarbons.
flammable in air. Can be safely stored under liquid hydrocarbons. Dangerous explosion hazard when exposed to moisture in any form!! Keep away from water at all times!! When heated in air it emits toxic fumes of sodium oxide. Reacts with water or steam to produce heat, hydrogen, and flammable vapors. Can react vigorously to explosively with oxidizing materials. To fight fEe, use soda ash, dry sodium chloride, or graphite, in order of preference. When heated to decomposition it emits toxic fumes of NazO. See also SODIUM HYDROXIDE and HYDROGEN. Heated sodium is spontaneously
| [Hazardous Substances Data]
7440-23-5(Hazardous Substances Data) |
| Raw materials And Preparation Products | Back Directory | [Raw materials]
Sodium chloride-->Barium chloride-->Strontium chloride | [Preparation Products]
2-ETHOXYPYRIMIDIN-4-YLAMINE-->4-Methylbenzene-1-carboximidamide hydrochloride-->6-AMINO-2-METHYLTHIO-3-METHYLURACIL-->2,4-DIOXO-4-THIOPHEN-2-YL-BUTYRIC ACID METHYL ESTER-->4-Methyl-2-thiophenecarboxylic acid-->Tiotropium bromide-->2-Heptanol-->10-(METHYLSULFONYL)CAPRAMIDE-->Sodium peroxide-->4-AMINO-2-(TRIFLUOROMETHYL)PYRIMIDINE-5-CARBOXYLIC ACID-->4,6-DIAMINO-2-MERCAPTOPYRIMIDINE-->4-AMINO-2-METHYL-PYRIMIDINE-5-CARBOXYLIC ACID-->4-CHLOROBENZAMIDINE HYDROIODIDE-->4-METHYL-BENZAMIDINE-->6-AMINO-1-METHYL-5-NITROSOURACIL-->2-AMINO-4-METHOXYPYRIMIDINE-->4,4,4-Trifluoro-1-phenyl-1,3-butanedione-->4-AMINOPYRIMIDINE-5-CARBONITRILE-->4-METHOXY-BENZAMIDINE-->4-METHOXYBENZAMIDINE, HYDROCHLORIDE-->2-amino-6-chloropyrimidin-4(3H)-one-->4-Chlorobenzene-1-carboximidamide hydrochloride-->GLYCIDYL ISOPROPYL ETHER-->2,2'-DIPYRIDYLAMINE-->4-AMINO-2-METHYLPYRIMIDINE-5-CARBONITRILE-->SODIUM PHENOLATE TRIHYDRATE-->2-Amino-6-hydroxypyrimidin-4(3H)-one ,97%-->3,3-Diphenylpropanol-->Chlorotriphenyltin-->bis(2-ethylhexyl) phenyl phosphite-->3-OCTANOL-->2-Amino-4-methoxypyridine-->2,4-DIMETHYLQUINOLINE-->2-Methyl-1-butanethiol-->ETHYL 3-AMINOTHIOPHENE-2-CARBOXYLATE-->4-AMINO-2-MERCAPTOPYRIMIDINE-5-CARBONITRILE-->2-METHOXYFURAN-->5-BROMO-2-CHLORO-4-METHOXYPYRIMIDINE-->ETHYL PICOLINOYLACETATE-->Ethyl alpha-Formyl Benzeneacetic Acid Ester |
| Hazard Information | Back Directory | [General Description]
A silvery soft metal that becomes grayish white upon exposure to air. Shipped as a solid or molten liquid. Burns violently with explosions that may spatter the material. Used for making gasoline additives, electric power cable, SODIUM(7440-23-5) lamps, other chemicals. | [Reactivity Profile]
SODIUM is a powerful reducing agent. Reacts with incandescence with boron trifluoride [Merck 11th ed. 1989]. Reacts explosively with maleic anhydride [Chem Safety Data Sheet SD-88 1962; Chem. Haz. Info. Series C-71 1960]. Explodes on contact with bromoazide. Mixtures with any of the following produce a strong explosion on impact: aluminum bromide, aluminum chloride, aluminum fluoride, ammonium chloride, antimony(III) bromide, antimony(III) chloride, antimony(III) iodide, arsenic(III) chloride, arsenic(III) iodide, bismuth(III) bromide, bismuth(III) chloride, bismuth(III) iodide, boron tribromide, carbon tetrachloride, chromium(IV) chloride, cobalt(II) bromide, cobalt(II) chloride, copper(II) chloride, iron(II) chloride, iron(III) bromide, iron(II) iodide, iodine bromide, manganese(II) chloride, mercury(II) bromide, mercury(II) chloride, mercury(II) fluoride, mercury(II) iodide, mercury(I) chloride, silicon tetrachloride, silver fluoride, tin(IV) chloride, tin(IV) iodide (with sulfur), tin(II) chloride, sulfur dibromide, sulfur dichloride, thallium(I) bromide, vanadium pentachloride, phosphorus pentachloride, phosphorus tribromide, and zinc bromide [Mellor 2 Supp. 2:497 1961]. Reacts with ammonium nitrate to form a yellow explosive substance, thought to be disodium nitrite [Mellor 8: Supp. 1 546 1964]. Reduces heated bismuth(III) oxide to the metal; the reaction is accompanied by incandescence [Mellor 9:649 1946-47]. Reacts, if finely divided, with bromine with luminescence. Burns spontaneously in moist chlorine. Reacts at room temperature with iodine [Mellor 2 Supp. 1:848 1956]. Reacts explosively with Dry Ice if the two are brought together by impact [Mellor 2 Supp. 2:468 1961]. Forms explosive mixtures with chlorinated hydrocarbons [Chem. Eng. News 26:2604 1948]. Explodes on contact with hydrochloric acid [Mellor 2:469 1946-47]. Explodes with aqueous hydrofluoric acid [Mellor 2:469 1946-47]. Ignites spontaneously in contact with dilute nitric acid [Mellor 2:470 1946-47]. Reacts with dilute sulfuric acid with explosive violence [Mellor 2:470 1946-47]. Sodium ignites on contact with hydroxylamine. (Mellor, 1940, Vol. 8, 292.) | [Air & Water Reactions]
May ignite spontaneously in air. Reacts violently with water to give sodium hydroxide and hydrogen, which ignites spontaneously [Merck, 11th ed. 1989)]. The ignition temperature of sodium in air depends on the area of surface exposed: vapor ignites at room temperature; droplets at about 250°F; an agitated pool at 400°F. In the absence of moisture and hydrogen, the reaction is insignificant [Mellor 2 Supp. 2:440 1961]. | [Hazard]
Severe fire risk in contact with water in any
form, ignites spontaneously in dry air when heated;
to extinguish fires use dry soda ash, salt, or lime.
Forms strong caustic irritant to tissue.
| [Health Hazard]
Severe burns caused by burning metal or by caustic soda formed by reaction with moisture on skin. | [Potential Exposure]
A potential danger to those involved in tetra-alkyl lead manufacture using lead-sodium alloy as a reactant; those using sodium as a liquid metal coolant, as a catalyst, or in the manufacture of sodium hydride, borohydride, or peroxide. | [Fire Hazard]
Special Hazards of Combustion Products: Fumes of burning Na are highly irritating to skin, eyes, and mucous membranes. | [First aid]
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 30 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. Wipe the chemical off the skin with a dry cloth. Then quickly remove contaminated clothing. Immediately wash area with large amounts of water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy. | [Shipping]
UN1428 Sodium, Hazard Class: 4.3; Labels: 4.3-Dangerous when wet material. Note: Finely divided sodium is pyrophoric. | [Incompatibilities]
A strong reducing agent. A dangerous fire hazard when exposed to heat and moisture. Violent reaction with water, forming NaOH. Violent reaction with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. halogenated hydrocarbons; phosphorus and phosphorus compounds; sulfur and sulfur compounds; and many other chemicals. | [Chemical Properties]
Sodium is a soft silvery white metallic element. Pyrophoric solid or molten liquid. Odorless, oxidizing rapidly in air; waxlike at room temperature, brittle at low temperatures. Store in airtight containers or in naphtha or similar liquid that does not contain water or free oxygen. Decomposes water on contact, with evolution of hydrogen to form sodium hydroxide; insoluble in benzene, kerosene, and naphtha. Has excellent elec- trical conductivity and high heat-absorbing capacity. | [Waste Disposal]
Incineration with absorption of oxide fumes. | [Physical properties]
Sodium is a soft, wax-like silver metal that oxidizes in air. Its density is 0.9674 g/cm3, andtherefore it floats on water as it reacts with the water releasing hydrogen. It has a rather lowmelting point (97.6°C) and a boiling point of 883°C. Sodium is an excellent conductor ofheat and electricity. It looks much like aluminum but is much softer and can be cut with aknife like butter. Its oxidation state is +1. | [Isotopes]
Sodium has 14 isotopes. The only stable isotope of sodium has an averageatomic weight of 23 (23Na) and makes up about 100% of all the isotopes of the element sodium found on Earth. All the other 13 isotopes (from 19Na to 31Na) are radioactive with relatively short half-lives and thus are unstable. | [Origin of Name]
The Latin name for the symbol for “sodium” (Na) is natrium, and the
name “sodium” in Latin is sodanum, which was known as an ancient headache remedy
and was called “soda” in English. | [Occurrence]
Sodium is the sixth most abundant of the Earth’s elements. Since it is a highly electropositive metal and so reactive with nonmetals, it is not found in its pure elemental form on Earth.Rather, it is found in numerous compounds in relatively abundant quantities. About 2.83%of the Earth’s crust consists of sodium in compounds.Sodium is produced by an electrolytic process, similar to the other alkali earth metals. (Seefigure 4.1). The difference is the electrolyte, which is molten sodium chloride (NaCl, common table salt). A high temperature is required to melt the salt, allowing the sodium cationsto collect at the cathode as liquid metallic sodium, while the chlorine anions are liberated aschlorine gas at the anode: 2NaCl (salt) + electrolysis → Cl2↑ (gas) + 2Na (sodium metal). Thecommercial electrolytic process is referred to as a Downs cell, and at temperatures over 800°C,the liquid sodium metal is drained off as it is produced at the cathode. After chlorine, sodiumis the most abundant element found in solution in seawater. | [Characteristics]
On the periodic table sodium is located between lithium and potassium. A fresh cut intosodium looks silvery but turns gray as sodium oxidizes rapidly in air, forming sodium oxideon its surface.Sodium is extremely reactive. It reacts explosively in water as it releases hydrogen fromthe water with enough heat to ignite the hydrogen. The resulting compound of this reactionis sodium hydroxide (2Na + 2H2O → 2NaOH + H2↑). Due to its extremely electropositivereactivity, there are few uses for the pure metallic form of sodium. Because of its reactivity,hundreds of sodium compounds are found on the Earth’s surface.Guide to the Elements | 51An unusual characteristic of several alkali metals is that a mixture of two or more has alower melting point than the melting point of the separate metals. This is referred to as aeutectic system of metallic alloys. For instance, sodium has a melting point of 97.6°C, andpotassium’s melting point is 63.25°C, but when the two are mixed, the eutectic melting point(turning into a liquid phase) of the combined Na-K system is below zero degrees Celsius(–10°C). If cesium metal (melting point of 38.89°C) is added to the Na and K mixture, themelting point of this eutectic alloy (Na-K-Cs) is the lowest of any eutectic alloy at –78°C. | [Preparation]
Sodium metal is produced commercially today by the electrolysis of fused sodium
chloride in a Downs cell. The Castner cell was the first commercially successful cell and
remained the principal source of sodium metal from about 1891 until being superseded by
the Downs cell6. This latter cell, introduced at duPont's Niagara Falls plant about 1921,
consists of a steel, refractory-brick-lined vessel with a graphite anode projecting upward from the bottom and a cast steel cathode surrounding the anode with an electrode spacing
of about 4 cm. The electrolyte is a eutectic mixture of roughly 40 % sodium chloride and
60 % calcium chloride, chosen so that the melting point of the mixed salt system is about
580°C, the operating temperature of the cell. The voltage drop across the cell is about
7 V and the current efficiency is roughly 85 %. As current flows through the molten salt
mixture, chlorine is liberated at the anode, and both sodium metal and calcium metal are
formed at the cathode; an iron gauze diaphragm between the electrodes prevents recombination.
The chlorine vapors from the anode flow overhead to a nickel collector dome
under slight vacuum, whence it is led to the chlorine purification and collection system.
The cathode product, a solution of calcium metal in liquid sodium, floats on the molten
salt bath and ascends through a vertical riser pipe into a collector vessel. As the solution
rises in the pipe, it is cooled to a temperature where calcium metal crystallizes, falls back into
the cell, and there reacts with the electrolyte. The sodium metal is filtered at 105-110°C to
remove calcium metal as well as small amounts of oxides and chlorides.
Many other methods for producing sodium metal have been devised, including electrolysis
of sodium carbonate, borate, nitrate, etc., but only the Castner-type cell based on
electrolysis of sodium hydroxide has had any appreciable commercial success. Today,
only the Downs-type cell is used commercially to produce sodium metal in most countries;
a few Castner-type cells are still operating, but total production is quite small.
| [Flammability and Explosibility]
Sodium spontaneously ignites when heated above 115 °C in air that has even
modest moisture content, and any sodium vapor generated is even more flammable.
Sodium reacts violently on contact with water and often ignites or explodes the
hydrogen formed. Sodium fires must be extinguished with a class D dry chemical
extinguisher or by the use of sand, ground limestone, dry clay or graphite, or "Met-
L-X ?" type solids. Water or CO2 extinguishers must never be used on sodium fires. | [Agricultural Uses]
Sodium (Na) is a silvery reactive element belonging to
Group 1 (formerly IA) of the Periodic Table.
It is not an essential element for any crop (including salt
marsh plants), but it is useful in certain biological
processes. Some crops grow better with sodium which is
absorbed as an ion.
Sodium influences water retention in sugar beet and
increases drought resistance. The supportive role of
sodium is not clear in some plants; however, in crops like
celery, marigold, sugar beet, turnip, etc., it increases the
amount of water held by a unit dry weight of the leaf
tissue and increases the succulence of the plant (which is
why these plants have a greater drought resistance and
increased leaf area.) Sugar beet and marigold in western
Europe, for instance, need a good supply of sodium for
satisfactory yields. In potassium deficient soils, sodium
helps the growth of crops like barley and prevents the
accumulation of other toxic cations, because deficiency
of one cation leads to accumulation of the other.
Sodium concentration varies widely from 0.01 to
10% in leaves. Sugar beet petioles frequently contain the
upper end of the range. In low-sodium soils, beet leaves
are dark green, thin and dull in hue and exhibit interveinal necrosis similar to that resulting from potassium
deficiency.
Sodium is essential for halophytic plants. Plants that
possess the C4 dicarboxylic acid photosynthetic pathway,
require sodium as an essential nutrient. Sodium has a role
in inducing crassulacean acid metabolism that is
responsible for water stress. The lack of sodium causes
certain plant species to shift their carbon dioxide fucation
pathway from C4 to C3. Water economy in plants seems to
be related to the C4 dicarboxylic photosynthetic pathway
of plants in fine textured soils. The benefits of sodium are
high when potassium is deficient.
The sodium demand of the crops is independent of,
and perhaps greater than, their potassium demand. The
important sodium-containing fertilizers are potassium
fertilizers with a wide ranging content of sodium
chloride, sodium nitrate, rhenania phosphate and
multiple nutrient fertilizers with sodium salts.
Sodium nitrate is available as a natural product, Chile
saltpeter, which contains trace amounts of
micronutrients, like boron. Synthetically, it is made from
nitric acid and sodium hydroxide.
The presence of sodium in soils is restricted to arid
and semi-arid regions. It is one of the most loosely held
metallic ions and is readily lost in leaching water. In fine
textured soils, sodium accumulation inhibits plant growth.
A high concentration of sodium is undesirable in
water as sodium is adsorbed on cation exchange sites,
causing soil aggregates to break down, sealing the soil
pores, and making it impermeable to water flow. Sodium
adsorption ratio (SAR) is used to estimate the
exchangeable percent sodium of soil; a low value
indicates low sodium content.
In sodic soils, exchangeable sodium is above 15 % and
its adsorption rate (SAR) is 13. The permeability is the
limiting factor in the reclamation of sodic soil. A high salt
content in water keeps sodic soils flocculated (joining of
colloidal particles to form clusters) and the floccules are
highly porous and allow penetration of the leaching
waters. Thus, the first water used for leaching may be
moderately salty. Sodic soil with low salt concentrations
readily loses its structure because it allows soil colloids
(clay and humus) to disperse into individual hydrated
particles.
Some of the effects ascribed to sodium may also be
due to the chloride ion in sodium chloride. In addition to
toxicity due to high concentrations of sodium and
chloride, sodium chloride affects plant growth because of
the osmotic effect which increases the potential forces
that hold water in the soil and makes it difficult for the
plant roots to extract moisture.
Fine textured clayey soils with low exchangeable
sodium (10%) and sandier soils with 20% exchangeable
sodium experience dispersion damage. Colloid dispersal
makes the soil impermeable to water and affects plant
growth. The impermeability to water causes soils to form
hard surface cmsts when dry. Uncorrected sodicity
makes most soils inhospitable to vegetation and agriculture. | [Pharmaceutical Applications]
Sodium has atomic number 11 and has the symbol Na, derived from the Latin name natrium. Sodium ions (Na+) are soluble in water and therefore present in large quantities in the oceans. Na+ is also part of minerals and an essential element for all animal life. The main biological roles of sodium ions are the maintenance of body fluids in humans and the functioning
of neurons and transmission of nerve impulses. Na+ is an important electrolyte and a vital component of the
extracellular fluid. Therefore, one of its roles is to maintain the fluid in the human body via osmoregulation,
a passive transport mechanism. Na+ ions also play a crucial role in the contraction of muscles
and in the mode of action of several enzymes. In the human body, Na+ is often used to actively build up an
electrostatic potential across membranes, with potassium ions (K+) being the counter-ion.
The build-up of an electrostatic potential across cell membranes is important to allow the transmission of
nerve impulses.
Sodium is an essential mineral for the human body and crucial for the regulation of the body fluid via its osmosis activity. Sodium ions account for over 90% of all ions in the plasma and in the interstitial fluid, which are involved in osmosis processes. Furthermore, it is the most abundant cation in the extracellular fluid, and therefore the Na+ content controls the extracellular volume. In particular, the kidneys play an important role in regulating the fluid level of the body as well as the filtration, secretion and re-absorption of Na+ in the nephrons, the functional unit of the kidney. Na+ ions are used in the human body to establish osmotic gradients, which in turn is crucial to control the water balance. Furthermore, decreases in blood pressure and in Na+ concentrations are sensed by the kidneys, and hormones (e.g. renin, antidiuretic hormones (ADHs), atrial natriuretic peptide) are released that control the blood pressure, osmotic balances and water-retaining mechanisms. | [Environmental Fate]
Elemental sodium that is released into the environment reacts
almost immediately with water to form sodium hydroxide and
hydrogen gas. Even small quantities of metallic sodium can be
explosive when brought into contact with sources of water; the
formation sodium hydroxide raises the local pH and is
extremely caustic. Sodium cations formed from this reaction
are rapidly absorbed into the surrounding environment to
form a large variety of salts. | [storage]
Safety glasses,
impermeable gloves, and a fire-retardant laboratory coat should be worn at all times
when working with sodium, and the metal should be handled under the surface of an
inert liquid such as mineral oil, xylene, or toluene. Sodium should be used only in
areas free of ignition sources and should be stored under mineral oil in tightly
sealed metal containers under an inert gas such as argon. | [Purification Methods]
The metal is placed on a coarse grade of sintered-glass filter, melted under vacuum and forced through the filter using argon. The Pyrex apparatus is then re-evacuated and sealed off below the filter, so that the sodium could be distilled at 460o through a side arm and condenser into a receiver bulb which is then sealed off [Gunn & Green J Am Chem Soc 80 4782 1958]. EXPLODES and IGNITES in water. | [Toxicity evaluation]
The formation of hydroxide ion following reaction of pure
sodium with water in biological tissues is the primary mechanism
of toxicity for sodium metal. The presence of the strong
base raises the local pH and can lead to burns and/or irritation
of the affected area. |
| Questions And Answer | Back Directory | [Description]
Sodium was first isolated by Sir Humphry Davy in 1807 by electrolysis of caustic soda. In the following year, Gay Lussac and Thenard obtained metallic sodium by chemical reduction of caustic soda with iron at elevated temperatures. Deville, in 1854, prepared the metal by reduction of sodium carbonate and lime with charcoal at a temperature above the boiling point of sodium. Castner, in 1886, improved the chemical reduction process preparing the metal by heating sodium hydroxide with iron carbide at high temperature. Five years later he patented a process based on electrolytic reduction of sodium hydroxide. The first major commercial plant was set up in 1921 with the introduction of Downs cell.
The element derived its name from the Latin word sodanum meaning “headache remedy.” Its symbol Na was derived from the Latin word, natrium.
Sodium is the sixth most abundant element on earth. It comprises about 2.6% weight of the earth’s crust. Its salt, sodium chloride, is the major component of seawater. The concentration of sodium in seawater is 1.08%. As a very reactive element, sodium is never found in free elemental form. It occurs in nature in many minerals such as cryolite, amphibole, zeolite, sodalite, and soda niter. Sodium chloride (NaCl) is the most common salt of sodium. Some other important salts are caustic soda (NaOH), soda ash (Na2CO3), baking soda (NaHCO3), Chile saltpeter (NaNO3), borax (Na2B4O7•10H2O), sodium thiosulfate (Na2S2O3), sodium sulfate (Na2SO4), and sodium phosphates.
| [Uses]
Metallic sodium is a strong reducing agent, used in many organic syntheses. It is used in the manufacture of sodamide, sodium peroxide, and esters. Other uses are in purifying molten metals, to descale metal, to improve structure of certain alloys, and as a heat transfer agent, for example, in nuclear reactors.
Sodium is useful in producing other metals, such as titanium. It is used in sodium vapor lamps in small amounts. Sodium wire is used to remove traces of water from organic solvents.
| [Production Methods]
Sodium metal is produced by both electrolytic and chemical reduction processes. All commercial processes employed today are based on electrolytic methods. Such processes are in wide use since Davy prepared the metal the first time in 1807.
There are two electrolytic methods that are of major importance. One involves the electrolysis of fused sodium chloride using the Downs cell. This method currently is most prevalent. The Downs cell consists of a steel cell with brick lining containing the fused bath. The multiple electrode arrangement consists of four cylindrical graphite anodes that project upward from the base of the cell. Each anode is surrounded by a diaphragm of iron gauge and a steel cathode.
Fused sodium chloride is electrolyzed at bath temperature varying between 565 to 600°C at a cell voltage of 5.7 to 7 V and the cell current varying from 25 to 35 kA. The cathode current density is mostly about 9.8 kA/m2. Often calcium chloride is added to sodium chloride in the cell bath to lower its melting point. Calcium is largely removed from sodium by filtration at about 110°C. Other electrolyte compositions have been used in which calcium is partially or fully replaced. The cell feed must be free of sulfate and other impurities.
Electrolysis of fused sodium hydroxide has been achieved successfully with a Castner cell. The Castner cell was used in commercial production prior to introduction of Downs cell. The cell is operated at a bath temperature 320 ± 10°C, at 9.0 ± 0.5 amp current and a voltage of 4.3 to 5.0 V. The cathode current density is about 10.9 kA/m2. The cell consists of a copper cathode and a nickel anode and a cylindrical iron-gauge diaphragm placed between the electrodes. The cell reactions are as follows:
cathode: 4Na+ + 4e¯ → 4Na
SODIUM 847anode: 4OH¯ – 4e¯ → 2H2O + O2
Water generated at the anode diffuses through the diaphragm and goes to the cathode, reacting with sodium to form sodium hydroxide.
2H2O + 2Na → 2NaOH + H2
The overall change may be represented as:
2NaOH → 2Na + H2 + O2
Because water is reacting with sodium produced at the cathode, the yield of sodium is reduced almost by 50%. Lesser yield is the major disadvantage of the Castner process. At present, this process is not used commercially.
Thermal reduction processes are not being practiced anywhere in the world at present for large-scale production of sodium. Such methods, however, can be conveniently adapted for laboratory preparation of metallic sodium. Sodium can be prepared by thermal reduction of its hydroxide, carbonate, or chloride at elevated temperatures. These salts are heated with carbon, calcium carbide, iron carbide, ferrosilicon, or other reducing agents at temperatures above 800°C under vacuum:
6NaOH + 2C → 2Na + 2Na2CO3 + 3H2
Na2CO3 + 2C → 2Na + 3CO
2NaCl + CaC2 → 2Na + CaCl2 + 2C
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