Sodium (Na)
alkali-metalSolid
Standard Atomic Weight
22.989769 uElectron configuration
[Ne] 3s1Melting point
97.8 °CBoiling point
882.85 °CDensity
970 kg/m³Oxidation states
−1, 0, +1Electronegativity (Pauling)
0.93Ionization energy (1st)
5.139077 eVDiscovery year
1807Atomic radius
180 pmDetails
Sodium is a soft, highly reactive alkali metal in group 1. It has one valence electron and almost always forms Na⁺ in ordinary compounds. The element is abundant in seawater, evaporite deposits, and silicate minerals, but it is never found free in nature because it reacts readily with water, oxygen, and many nonmetals. Its salts are central to physiology, glassmaking, detergents, and bulk chemical manufacture.
Sodium, like every reactive element, is never found free in nature. Sodium is a soft, bright, silvery metal which floats on water. Decomposition in water results in 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.
The name derives from the English soda and Latin sodanum for "headache remedy". The symbol Na derives from the Latin natrium for "natron" (soda in English). Sodium was discovered in 1807 by the English chemist Humphry Davy from electrolysis of caustic soda (NaOH).
Although sodium is the sixth most abundant element on earth and comprises about 2.6% of the earth's crust, it is a very reactive element and is never found free in nature. Pure sodium was first isolated by Sir Humphry Davy in 1807 through the electrolysis of caustic soda (NaOH). Since sodium can ignite on contact with water, it must be stored in a moisture free environment.
From the English word, soda; Medieval Latin, sodanum: a headache remedy. Long recognized in compounds, sodium was first isolated by Davy in 1807 by electrolysis of caustic soda.
Pure sodium is a silvery, lustrous metal when freshly cut. It is soft enough to cut with a knife and quickly tarnishes in air as surface oxides, hydroxide, and carbonate form. At ordinary temperature it is a low-density solid with a relatively low melting point for a metal.
Metallic sodium is used mainly as a chemical reductant and heat-transfer medium where its high thermal conductivity and low neutron moderation are useful, notably in some fast-reactor designs. Sodium vapor lamps were historically important for efficient yellow street lighting. Sodium compounds have far larger uses: sodium chloride (NaCl) for food, deicing, and chlor-alkali feedstock; sodium carbonate (Na₂CO₃) for glass and detergents; and sodium hydroxide (NaOH) for pulp, alumina, soaps, and many chemical processes.
Sodium is used in the production of titanium, sodamide, sodium cyanide, sodium peroxide, and sodium hydride. Liquid sodium has been used as a coolant for nuclear reactors. Sodium vapor is used in streetlights and produces a brilliant yellow light.
Sodium also forms many useful compounds. Some of the most common are: table salt (NaCl), soda ash (Na2CO3), baking soda (NaHCO3), caustic soda (NaOH), Chile saltpeter (NaNO3) and borax (Na2B4O7·10H2O).
Metallic sodium is vital in the manufacture of esters and in the preparation of organic compounds. The metal may be used to improve the structure of certain alloys, descale metal, and purify molten metals.
An alloy of sodium with potassium, NaK, is an important heat transfer agent.
Isotopes in Biology
Both 22Na and 24Na have been used as radioactive tracers to study electrolytes in the human body [108] World Nuclear Association. Radioisotopes in Industry: Industrial Uses of Radioisotopes, World Nuclear Association (2014), Feb. 24; http://www.world-nuclear.org/info/inf56.html., [109] Australian Government, Australian Nuclear Science and Technology Organisation (Ansto). [Radioisotopes]:/their Role in Society Today/, Australian Government, Australian Nuclear Science and Technology Organisation (Ansto) (2014), Feb. 24; http://www.ansto.gov.au/__data/assets/pdf_file/0018/3564/Radioisotopes.pdf., [110] AUS-e-TUTE for Astute Science Students. Chemistry Tutorial: Summary of Radioactive Particles, Isotopes, Properties and Uses, AUS-e-TUTE for Astute Science Students (2014), Feb. 24; http://www.ausetute.com.au/nuclesum.html..
Isotopes in Geochronology
22Na is a cosmogenic isotope with a half-life of 2.6 years that has been used to study the residence time of water in freshwater basins. It has been used for dating of young (up to a few decades old) surface water and groundwater (Fig. IUPAC.11.1) [111] D. G. Fleishman. J. Environ. Radioact.99, 1203 (2008)..
Isotopes in Medicine
22Na is used as a source to calibrate positron emission tomography (PET) imaging scanners to check that the instruments are functioning properly [112] T. Hasegawa, K. Oda, Y. Wada, Y. Sato, T. Yamada, M. Matsumoto, H. Murayama, T. Takeda, T. Sasaki, K. Kikuchi, Y. Abe, H. Miyatake, K. Miwa, K. Akimoto, K. Wagatsuma. “Application of novel calibration scheme based on traceable point-like 22Na sources to various types of PET scanners”, in Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2012 IEEE..
Sodium chemistry is dominated by the +1 oxidation state and ionic salts containing Na⁺. Sodium chloride (NaCl) is the most familiar salt and a major industrial feedstock. Sodium hydroxide (NaOH) is a strong base, sodium carbonate (Na₂CO₃) and sodium bicarbonate (NaHCO₃) are important alkaline carbonates, and sodium sulfate (Na₂SO₄) is used in detergents and glass. Sodium hydride (NaH) is a strong base and hydride donor in synthesis. Organosodium compounds exist but are generally more reactive and less commonly handled than organolithium reagents.
The most common compound is sodium chloride (table salt), but it occurs in many other minerals, such as soda niter, cryolite, amphibole, zeolite, etc.
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), di- and tri-sodium phosphates, sodium thiosulfate (hypo, Na2S2O3 • 5H2O), and borax (Na2B4O7 • 10H2O).
See more information at the Sodium compound page.
Metallic sodium reacts violently with water to form sodium hydroxide (NaOH) and hydrogen (H₂), which can ignite from the heat released. It is stored under dry mineral oil or inert gas and must be kept away from moisture, acids, and halogenated solvents. Concentrated sodium hydroxide and some other sodium compounds are corrosive. Sodium ions are essential in the body, but excessive dietary sodium is associated with adverse health effects in susceptible populations.
Sodium metal should be handled with great care. It cannot be maintained in an inert atmosphere and contact with water and other substances with which sodium reacts should be avoided.
Sodium is widely distributed in rocks, soils, natural brines, and oceans. Weathering releases Na⁺ from feldspars and other silicates, and rivers carry it to lakes and the sea, where it remains highly soluble. In arid regions it can accumulate in soils and impair plant growth by increasing salinity and altering soil structure. Road deicing salts can raise sodium and chloride levels in nearby waters and soils.
The main commercial sodium materials are salts rather than the metal. Sodium chloride is mined as rock salt, extracted from brines, and recovered by solar evaporation; it feeds chlor-alkali plants that make chlorine (Cl₂), hydrogen (H₂), and sodium hydroxide (NaOH). Sodium carbonate is produced from natural trona deposits or by synthetic processes such as the Solvay route. Metallic sodium is made by electrolysis of molten sodium chloride or related salt mixtures and has a much smaller, specialized market. Recycling is usually process-specific rather than a broad commodity loop.
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 fourth 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.
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 moderately abundant light element produced chiefly by stellar nucleosynthesis involving carbon and neon burning and by related neutron-capture reactions in stars. Its yellow D spectral lines are strong and easily observed in stellar atmospheres, comets, planetary exospheres, and interstellar gas. On rocky planets it is commonly incorporated into silicates and soluble salts rather than existing as metal.
- Sodium’s chemical symbol comes from natrium, a Latinized name related to soda minerals.
- The yellow sodium D lines near 589 nm are among the most recognizable atomic emission features.
- Liquid sodium has been used as a coolant because it stays liquid over a broad temperature range.
- Fresh sodium surfaces can look mirror-bright before tarnishing within seconds in moist air.
- Common table salt usually contains additives, so it is not pure sodium chloride.
Images
Properties
Physical
- Atomic radius (empirical)
- 180 pm Compare Atomic radius (empirical) of all elements →
- Covalent radius
- 166 pm Compare Covalent radius of all elements →
- Van der Waals radius
- 227 pm Compare Van der Waals radius of all elements →
- Metallic radius
- 157 pm Compare Metallic radius of all elements →
- Density
- 970 kg/m³ Compare Density of all elements →
- Molar volume
- 0.0237 L/mol
- Phase at STP
- Solid Compare Phase at STP of all elements →
- Melting point
- 97.8 °C Compare Melting point of all elements →
- Boiling point
- 882.85 °C Compare Boiling point of all elements →
- Thermal conductivity
- 142 W/(m·K) Compare Thermal conductivity of all elements →
- Specific heat capacity
- 1.228 J/(g·K) Compare Specific heat capacity of all elements →
- Molar heat capacity
- 28.23 J/(mol·K) Compare Molar heat capacity of all elements →
- Crystal structure
- Body-centered cubic Compare Crystal structure of all elements →
Chemical
- Electronegativity (Pauling)
- 0.93 Compare Electronegativity (Pauling) of all elements →
- Electronegativity (Allen)
- 0.869
- Electron affinity
- 0.5479 eV
- Ionization energy (1st)
- 5.139077 eV Compare Ionization energy (1st) of all elements →
- Ionization energy (2nd)
- 47.286523 eV Compare Ionization energy (2nd) of all elements →
- Ionization energy (3rd)
- 71.620247 eV Compare Ionization energy (3rd) of all elements →
- Ionization energy (4th)
- 98.936341 eV Compare Ionization energy (4th) of all elements →
- Ionization energy (5th)
- 138.404476 eV Compare Ionization energy (5th) of all elements →
- Oxidation states
- −1, 0, +1 Compare Oxidation states of all elements →
- Valence electrons
- 1 Compare Valence electrons of all elements →
- Electron configuration
- [Ne] 3s1
Thermodynamic
- Critical point (temperature)
- 2300 °C
- Critical point (pressure)
- 3.5e+7 Pa
- Heat of fusion
- 0.02694719 eV Compare Heat of fusion of all elements →
- Heat of vaporization
- 1.012593 eV Compare Heat of vaporization of all elements →
- Heat of sublimation
- 1.11209 eV
- Heat of atomization
- 1.11209 eV
- Atomization enthalpy
- 1.114163 eV
Nuclear
- Protons
- 11 Compare Protons of all elements →
- Neutrons
- 12 Compare Neutrons of all elements →
- Known isotopes
- 23 Compare Known isotopes of all elements →
- Stable isotopes
- 1 Compare Stable isotopes of all elements →
- Most stable isotope
- Na-23
- Discovery year
- 1807
Abundance
- Abundance (Earth's crust)
- 2.36e+4 mg/kg Compare Abundance (Earth's crust) of all elements →
- Abundance (ocean)
- 1.08 × 104 mg/L Compare Abundance (ocean) of all elements →
Crystal Structure
- Lattice constant a
- 423 pm
Electronic Structure
- Electrons per shell
- 2, 8, 1 Compare Electrons per shell of all elements →
Identifiers
- CAS number
- 7440-23-5 Compare CAS number of all elements →
- Term symbol
- 2S1/2
- InChI
- InChI=1S/Na
- InChI Key
- KEAYESYHFKHZAL-UHFFFAOYSA-N
Electron Configuration Measured
Na: 3s¹[Ne] 3s¹1s² 2s² 2p⁶ 3s¹Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|---|---|---|
| 23 Stable | 22.989769282 ± 0.0000000019 | 100.0000% | Stable |
Phase / State
Reason: 72.8 °C below melting point (97.8 °C)
Schematic, not to scale
Phase transition points
Transition energies
Energy required to melt 1 mol at melting point
Energy required to vaporize 1 mol at boiling point
Energy required to sublime 1 mol at sublimation point
Density
At standard conditions
At standard conditions
Advanced
Atomic Spectra
Showing 10 of 11. Sorted by ion charge (ascending).
Lines Holdings ?
| Ion | Charge | Total lines | Transition probabilities | Level designations |
|---|---|---|---|---|
| Na I | 0 | 869 | 523 | 858 |
| Na II | +1 | 1345 | 176 | 605 |
| Na III | +2 | 560 | 417 | 560 |
| Na IV | +3 | 687 | 671 | 687 |
| Na V | +4 | 529 | 503 | 527 |
| Na VI | +5 | 657 | 594 | 641 |
| Na VII | +6 | 1374 | 1369 | 1374 |
| Na VIII | +7 | 464 | 456 | 464 |
| Na IX | +8 | 172 | 138 | 172 |
| Na X | +9 | 594 | 586 | 594 |
Levels Holdings ?
| Ion | Charge | Levels |
|---|---|---|
| Na I | 0 | 430 |
| Na II | +1 | 165 |
| Na III | +2 | 120 |
| Na IV | +3 | 104 |
| Na V | +4 | 102 |
| Na VI | +5 | 116 |
| Na VII | +6 | 142 |
| Na VIII | +7 | 89 |
| Na IX | +8 | 46 |
| Na X | +9 | 111 |
Ionic Radii
| Charge | Coordination | Spin | Radius |
|---|---|---|---|
| +1 | 4 | N/A | 99 pm |
| +1 | 5 | N/A | 100 pm |
| +1 | 6 | N/A | 102 pm |
| +1 | 7 | N/A | 112.00000000000001 pm |
| +1 | 8 | N/A | 118 pm |
| +1 | 9 | N/A | 124 pm |
| +1 | 12 | N/A | 139 pm |
Compounds
Isotopes (1)
Thirteen isotopes of sodium are recognized.
| Mass number | Atomic mass (u) | Natural abundance | Half-life | Decay mode | |
|---|---|---|---|---|---|
| 23 Stable | 22.989769282 ± 0.0000000019 | 100.0000% | Stable | stable |
Spectral Lines
Showing 50 of 480. Only spectral lines with measured intensity are shown by default.
| Wavelength (nm) | Intensity | Ion stage | Type | Transition | Accuracy | Source | |
|---|---|---|---|---|---|---|---|
| 588.995094 nm | 80000 | Na I | emission | 2p6.3s 2S → 2p6.3p 2P* | Measured | NIST | |
| 589.592424 nm | 40000 | Na I | emission | 2p6.3s 2S → 2p6.3p 2P* | Measured | NIST | |
| 388.181 nm | 420 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4D → 2p5.3s.(3P*).3d 4F* | Measured | NIST | |
| 443.234 nm | 310 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4S → 2p5.3s.(3P*).4s 4P* | Measured | NIST | |
| 411.3703 nm | 300 | Na II | emission | 2s2.2p5.3p 1S → 2s2.2p5.(2P*<1/2>).3d 2[3/2]* | Measured | NIST | |
| 507.12 nm | 270 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4D → 2p5.3s.(3P*).4s 4P* | Measured | NIST | |
| 412.3069 nm | 250 | Na II | emission | 2s2.2p5.3p 1S → 2s2.2p5.(2P*<1/2>).4s 2[1/2]* | Measured | NIST | |
| 423.335 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[7/2] | Measured | NIST | |
| 424.09 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[7/2] | Measured | NIST | |
| 429.249 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[1/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 429.287 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[1/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 430.882 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[1/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 430.904 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[1/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 432.091 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 433.729 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 434.412 nm | 250 | Na II | emission | 2s2.2p5.3p 1S → 2s2.2p5.(2P*<3/2>).4s 2[3/2]* | Measured | NIST | |
| 439.281 nm | 250 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[9/2] | Measured | NIST | |
| 408.1372 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[3/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST | |
| 436.859 nm | 200 | Na II | emission | 2s2.2p5.3p 1S → 2s2.2p5.(2P*<3/2>).3d 2[3/2]* | Measured | NIST | |
| 437.522 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 438.748 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 440.512 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[9/2] | Measured | NIST | |
| 444.669 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST | |
| 444.741 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[7/2] | Measured | NIST | |
| 445.473 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST | |
| 445.523 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<1/2>).4f 2[7/2] | Measured | NIST | |
| 445.72 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).4s 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 447.463 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).4s 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 447.88 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[3/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST | |
| 448.167 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 449.015 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 449.088 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 449.961 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 450.697 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 451.92 nm | 200 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[3/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST | |
| 452.497 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 453.331 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).4s 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 455.152 nm | 200 | Na II | emission | 2s2.2p5.(2P*<3/2>).4s 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[3/2] | Measured | NIST | |
| 391.803 nm | 160 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4D → 2p5.3s.(3P*).3d 4F* | Measured | NIST | |
| 438.42 nm | 160 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 439.63 nm | 160 | Na II | emission | 2s2.2p5.(2P*<3/2>).3d 2[7/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 459.094 nm | 160 | Na II | emission | 2s2.2p5.3p 1S → 2s2.2p5.(2P*<3/2>).3d 2[1/2]* | Measured | NIST | |
| 472.23 nm | 160 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 473.113 nm | 160 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[7/2] | Measured | NIST | |
| 474.163 nm | 160 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[5/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 476.892 nm | 160 | Na II | emission | 2s2.2p5.(2P*<1/2>).3d 2[3/2]* → 2s2.2p5.(2P*<3/2>).4f 2[5/2] | Measured | NIST | |
| 418.546 nm | 150 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4P → 2p5.3s.(3P*).3d 4D* | Measured | NIST | |
| 386.543 nm | 130 | Na I | emission | 2p5.(2P*).3s.3p.(3P*) 4D → 2p5.3s.(3P*).3d 4F* | Measured | NIST | |
| 408.7593 nm | 130 | Na II | emission | 2s2.2p5.3s 1P* → 2s2.2p5.3p 3S | Measured | NIST | |
| 420.2759 nm | 130 | Na II | emission | 2s2.2p5.(2P*<3/2>).4s 2[3/2]* → 2s2.2p5.(2P*<1/2>).4f 2[5/2] | Measured | NIST |
Extended Properties
Covalent Radii (Extended)
- Covalent radius (Pyykkö)
- 155 pm
- Covalent radius (Pyykkö, double)
- 160 pm
- Covalent radius (Bragg)
- 177 pm
Van der Waals Radii
- Bondi
- 227 pm
- Batsanov
- 240 pm
- Alvarez
- 250 pm
- UFF
- 298.3 pm
- MM3
- 270 pm
Atomic & Metallic Radii
- Atomic radius (Rahm)
- 225 pm
- Metallic radius (C12)
- 190 pm
Numbering Scales
- Mendeleev
- 2
- Pettifor
- 11
- Glawe
- 11
Electronegativity Scales
- Ghosh
- 0
- Miedema
- 3
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
Polarizability & Dispersion
- Dipole polarizability
- 162.7 a.u.
- Dipole polarizability (unc.)
- 0.5 a.u.
- C₆
- 1518 Ha·Bohr6
- C₆ (Gould–Bučko)
- 1570 Ha·Bohr6
Miedema Parameters
- Miedema molar volume
- 23.78 cm3/mol
- Miedema electron density
- 1
Supply Risk & Economics
- Production concentration
- 24
- Relative supply risk
- 4
- Political stability (top producer)
- 24
Phase Transitions & Allotropes
| Melting point | 370.94 K |
| Boiling point | 1156.09 K |
| Critical point (temperature) | 2573.15 K |
| Critical point (pressure) | 35 MPa |
Oxidation State Categories
Advanced Reference Data
Screening Constants (4)
| n | Orbital | σ |
|---|---|---|
| 1 | s | 0.3741 |
| 2 | p | 4.1982 |
| 2 | s | 4.4286 |
| 3 | s | 8.4926 |
Crystal Radii Detail (7)
| Charge | CN | Spin | rcrystal (pm) | Origin |
|---|---|---|---|---|
| 1 | IV | 113 | ||
| 1 | V | 114 | ||
| 1 | VI | 116 | ||
| 1 | VII | 126 | ||
| 1 | VIII | 132 | ||
| 1 | IX | 138 | calculated, | |
| 1 | XII | 153 |
Isotope Decay Modes (47)
| Isotope | Mode | Intensity |
|---|---|---|
| 17 | p | 100% |
| 18 | p | — |
| 19 | p | 100% |
| 20 | B+ | 100% |
| 20 | B+A | 25% |
| 21 | B+ | 100% |
| 22 | B+ | 100% |
| 22 | e+ | 90.6% |
| 22 | EC | 9.4% |
| 24 | B- | 100% |
X‑ray Scattering Factors (504)
| Energy (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 0.01475 |
| 10.1617 | — | 0.01517 |
| 10.3261 | — | 0.01559 |
| 10.4931 | — | 0.01603 |
| 10.6628 | — | 0.01648 |
| 10.8353 | — | 0.01695 |
| 11.0106 | — | 0.01743 |
| 11.1886 | — | 0.01792 |
| 11.3696 | — | 0.01842 |
| 11.5535 | — | 0.01894 |
Additional Data
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
2.36×104 milligrams per kilogram
References (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
1.08×104 milligrams per liter
References (1)
Sources
Sources of this element.
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 fourth 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.
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.
References (1)
- [6] Sodium https://periodic.lanl.gov/11.shtml
References
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Sodium.
The element property data was retrieved from publications.