Potassium

Potassium (K)

Potassium is the 19th element in the periodic table and has a symbol of K and atomic number of 19. It has an atomic weight of 39.0983 and a mass number of 39. Potassium has nineteen protons and twenty neutrons in its nucleus, and nineteen electrons in four shells. It is located in group one, period four and block s of the periodic table. Soft silvery metallic element belonging to group 1 of the periodic table (alkali metals). Occurs naturally in seawater and a many minerals. Highly reactive, chemically, it resembles sodium in its behavior and compounds. Discovered by Sir Humphry Davy in 1807.
Atomic Number19
Atomic Weight39.0983
Mass Number39
Group1
Period4
Blocks
Protons19 p+
Neutrons20 n0
Electrons19 e-
Animated Bohr Model of K (Potassium)

Physical Properties

Atomic Radius
Molar Volume
Covalent Radius
Metallic Radius
Ionic Radius
Crystal Radius
Van der Waals Radius
Density
Atomic Radii of the Elements: Potassium0102030405060708090100110120130140150160170180190200210220230240250260270280pmAtomic RadiusCovalent RadiusMetallic RadiusVan der Waals Radius

Chemical Properties

Energy
Proton Affinity
Electron Affinity
Ionization Energy
Ionization Energies of K (Potassium)
Heat of Vaporization
Heat of Fusion
Heat of Formation
Electrons
Electron Shells2, 8, 8, 1
Bohr Model: K (Potassium)
Valence Electrons1
Lewis Structure: K (Potassium)
Electron Configuration[Ar] 4s1
1s2 2s2 2p6 3s2 3p6 4s1
Enhanced Bohr Model of K (Potassium)
Orbital Diagram of K (Potassium)
Oxidation States-1, 1
Electronegativity
0.82
Electrophilicity Index
States of Matter
PhaseSolid
Gas Phase
Boiling Point
Melting Point
Critical Pressure
Critical Temperature
Triple Point
Visual

Potassium is a Silver. K has a CPK of #ff1493, Jmol of #8f40d4, and MOLCAS GV of #8f40d4. The Appearance of Element 19 is silvery gray.

Color
Silver
Appearancesilvery gray
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
Electrical Resistivity
Superconducting Point
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.0000000067 m³/Kg
Magnetic Susceptibility (Molar)
0.000000000262 m³/mol
Magnetic Susceptibility (Volume)
0.00000574
Magnetic Ordering
Curie Point
Neel Point
Structure

The Crystal Structure of Potassium is BCC. The lattice constant of K is 5.23 Å. The lattice angles of Element 19 are π/2, π/2, π/2.

Crystal StructureBody Centered Cubic (BCC)
Lattice Constant
Lattice Anglesπ/2, π/2, π/2
Mechanical Properties

Potassium has a Brinell of 0.363 MPa, and Mohs hardness of 0.4 MPa. The Bulk Modulus of K is 3.1 GPa. The Shear Modulus of Element 19 is 1.3 GPa. The Speed of Sound of Potassium (K) is 2000 m/s.

Hardness
Bulk Modulus
Shear Modulus
Young's Modulus
Poisson Ratio
Speed of Sound
Classification

The CAS Group of Potassium is IA. The IUPAC Group of K is IA. The Glawe Number of Element 19 is 10. The Mendeleev Number of Potassium (K) is 3. The Pettifor Number of Potassium is 10. The Geochemical Class of K is alkali metal. The Goldschmidt Class of Element 19 is litophile.

CategoryAlkali metals, Alkali metals
CAS GroupIA
IUPAC GroupIA
Glawe Number10
Mendeleev Number3
Pettifor Number10
Geochemical Classalkali metal
Goldschmidt Classlitophile

Other

The Dipole Polarizability of Potassium is 289.7 plus or minus 0.3 a₀. K has a C6 Dispersion Coefficient (CD) of 3923 a₀, and C6 Dispersion Coefficient (GB) of 3910 a₀. The Allotropes of Element 19 is . The Neutron Cross Section of Potassium (K) is 2.1. The Neutron Mass Absorption of Potassium is 0.0018. The Quantum Numbers of K is 2S1/2. The Space Group of Element 19 is 229 (Im_3m).

Gas Basicity
Dipole Polarizability
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
2.1
Neutron Mass Absorption
0.0018
Quantum Numbers2S1/2
Space Group229 (Im_3m)

Isotopes of Potassium

Stable Isotopes2
Unstable Isotopes27
Natural Isotopes3
Isotopic Composition3993.26%3993.26%416.73%416.73%400.01%400.01%

31K

Mass Number31
Neutron Number12
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2019
Parity+

Decay ModeIntensity
3p100%

32K

Mass Number32
Neutron Number13
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin1
Quadrupole Moment
Discovery Year
Parity+

Decay ModeIntensity
p (proton emission)

33K

Mass Number33
Neutron Number14
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year
Parity+

Decay ModeIntensity
p (proton emission)

34K

Mass Number34
Neutron Number15
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin1
Quadrupole Moment
Discovery Year
Parity+

Decay ModeIntensity
p (proton emission)

35K

Mass Number35
Neutron Number16
Relative Atomic Mass
G-Factor
0.26133333333333 ± 0.0046666666666667
Abundance
Radioactivity☢️ Radioactive
Half Life
175.2 ± 1.9 ms
Spin3/2
Quadrupole Moment
Discovery Year1976
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)0.37%

36K

Mass Number36
Neutron Number17
Relative Atomic Mass
G-Factor
0.274 ± 0.0005
Abundance
Radioactivity☢️ Radioactive
Half Life
341 ± 3 ms
Spin2
Quadrupole Moment
Discovery Year1967
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)0.048%
β+α (β+-delayed α emission)0.0034%

37K

Mass Number37
Neutron Number18
Relative Atomic Mass
G-Factor
0.13547333333333 ± 0.00004
Abundance
Radioactivity☢️ Radioactive
Half Life
1.23651 ± 0.00094 s
Spin3/2
Quadrupole Moment
0.109 ± 0.004
Discovery Year1958
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

38K

Mass Number38
Neutron Number19
Relative Atomic Mass
G-Factor
0.457 ± 0.002
Abundance
Radioactivity☢️ Radioactive
Half Life
7.651 ± 0.019 m
Spin3
Quadrupole Moment
Discovery Year1937
Parity+

Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

39K

Mass Number39
Neutron Number20
Relative Atomic Mass
G-Factor
0.26098 ± 0.0000053333333333333
Abundance
93.2581 ± 0.0044
RadioactivityStable
Half LifeNot Radioactive ☢️
Spin3/2
Quadrupole Moment
0.0603 ± 0.0006
Discovery Year1921
Parity+

40K

Mass Number40
Neutron Number21
Relative Atomic Mass
G-Factor
Abundance
0.0117 ± 0.0001
Radioactivity☢️ Radioactive
Half Life
1.248 ± 0.003 Gy
Spin4
Quadrupole Moment
-0.075 ± 0.0008
Discovery Year1935
Parity-

Decay ModeIntensity
β (β decay)89.28%
β+ (β+ decay; β+ = ϵ + e+)10.72%

41K

Mass Number41
Neutron Number22
Relative Atomic Mass
G-Factor
0.143248 ± 0.0000033333333333333
Abundance
6.7302 ± 0.0044
RadioactivityStable
Half LifeNot Radioactive ☢️
Spin3/2
Quadrupole Moment
0.0734 ± 0.0007
Discovery Year1921
Parity+

42K

Mass Number42
Neutron Number23
Relative Atomic Mass
G-Factor
-0.57125 ± 0.0003
Abundance
Radioactivity☢️ Radioactive
Half Life
12.355 ± 0.007 h
Spin2
Quadrupole Moment
Discovery Year1935
Parity-

Decay ModeIntensity
β (β decay)100%

43K

Mass Number43
Neutron Number24
Relative Atomic Mass
G-Factor
0.10886666666667 ± 0.00053333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
22.3 ± 0.1 h
Spin3/2
Quadrupole Moment
Discovery Year1949
Parity+

Decay ModeIntensity
β (β decay)100%

44K

Mass Number44
Neutron Number25
Relative Atomic Mass
G-Factor
-0.428 ± 0.002
Abundance
Radioactivity☢️ Radioactive
Half Life
22.13 ± 0.19 m
Spin2
Quadrupole Moment
Discovery Year1954
Parity-

Decay ModeIntensity
β (β decay)100%

45K

Mass Number45
Neutron Number26
Relative Atomic Mass
G-Factor
0.1156 ± 0.00053333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
17.8 ± 0.6 m
Spin3/2
Quadrupole Moment
Discovery Year1964
Parity+

Decay ModeIntensity
β (β decay)100%

46K

Mass Number46
Neutron Number27
Relative Atomic Mass
G-Factor
-0.5255 ± 0.003
Abundance
Radioactivity☢️ Radioactive
Half Life
96.3 ± 0.08 s
Spin2
Quadrupole Moment
Discovery Year1965
Parity-

Decay ModeIntensity
β (β decay)100%

47K

Mass Number47
Neutron Number28
Relative Atomic Mass
G-Factor
3.866 ± 0.018
Abundance
Radioactivity☢️ Radioactive
Half Life
17.38 ± 0.03 s
Spin1/2
Quadrupole Moment
0
Discovery Year1964
Parity+

Decay ModeIntensity
β (β decay)100%

48K

Mass Number48
Neutron Number29
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
6.83 ± 0.14 s
Spin1
Quadrupole Moment
Discovery Year1972
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)1.14%

49K

Mass Number49
Neutron Number30
Relative Atomic Mass
G-Factor
2.6772 ± 0.0016
Abundance
Radioactivity☢️ Radioactive
Half Life
1.26 ± 0.05 s
Spin1/2
Quadrupole Moment
0
Discovery Year1972
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)86%

50K

Mass Number50
Neutron Number31
Relative Atomic Mass
G-Factor
0
Abundance
Radioactivity☢️ Radioactive
Half Life
472 ± 4 ms
Spin0
Quadrupole Moment
0
Discovery Year1972
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)28.6%
2n (2-neutron emission)

51K

Mass Number51
Neutron Number32
Relative Atomic Mass
G-Factor
0.342 ± 0.0013333333333333
Abundance
Radioactivity☢️ Radioactive
Half Life
365 ± 5 ms
Spin3/2
Quadrupole Moment
Discovery Year1983
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)65%
2n (2-neutron emission)

52K

Mass Number52
Neutron Number33
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
110 ± 4 ms
Spin2
Quadrupole Moment
Discovery Year1983
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)72.2%
2n (2-neutron emission)2.3%

53K

Mass Number53
Neutron Number34
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
30 ± 5 ms
Spin3/2
Quadrupole Moment
Discovery Year1983
Parity+

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)64%
2n (2-neutron emission)10%

54K

Mass Number54
Neutron Number35
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
10 ± 5 ms
Spin2
Quadrupole Moment
Discovery Year1983
Parity-

Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)
2n (2-neutron emission)

55K

Mass Number55
Neutron Number36
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2009
Parity+

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)

56K

Mass Number56
Neutron Number37
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin2
Quadrupole Moment
Discovery Year2009
Parity-

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)

57K

Mass Number57
Neutron Number38
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2018
Parity+

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)

58K

Mass Number58
Neutron Number39
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin2
Quadrupole Moment
Discovery Year2019
Parity-

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)

59K

Mass Number59
Neutron Number40
Relative Atomic Mass
G-Factor
Abundance
Radioactivity☢️ Radioactive
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2018
Parity+

Decay ModeIntensity
β (β decay)
β n (β-delayed neutron emission)
2n (2-neutron emission)
Kalium

History

Potassium's symbol K comes from 'kalium' the name of the element in Germany and Scandinavia. Potassium metal was first isolated in 1807 by Sir Humphry Davy, who derived it from caustic potash by the use of electrolysis of the molten salt with the newly discovered voltaic pile. Potassium was the first metal that was isolated by electrolysis. From the English word, potash - pot ashes; Latin kalium, Arab qali, alkali

DiscoverersSir Humphrey Davy
Discovery LocationEngland
Discovery Year1807
Etymology (Name Origin)English: pot ash; symbol from Latin: kalium, (alkali).
Pronunciationpe-TASS-i-em (English)
Potassium must be handled with great care with full skin and eye protection
People whose diets are low in potassium can suffer from hypokalemia

Uses

The greatest demand for potash has been in its use for fertilizers. Potassium is an essential constituent for plant growth and is found in most soils. Potassium nitrate is the main explosive ingredient in gunpowder. Potassium hydroxide is used in the manufacture of soft soaps and as an electrolyte in alkaline batteries. Used as potash in making glass & soap. Also as saltpeter, potassium nitrate (KNO3) to make explosives and to color fireworks in mauve. Formerly called kalium (K). Vital to function of nerve and muscle tissures.

Sources

Found in minerals like carnallite [(KMgCl3).6H2O] & sylvite (potassium chloride, KCL). Pure metal is produced by the reaction of hot potassium chloride and sodium vapors in a special retort.

Abundance
Abundance in Earth's crust
Natural Abundance (Oceans)
Natural Abundance (Human Body)
0.2 %
Natural Abundance (Meteor)
0.07 %
Natural Abundance (Sun)
0.0004 %
Abundance in Universe
0.0003 %

Nuclear Screening Constants

1s0.5105
2p3.9728
2s5.9938
3p11.2744
3s10.3201
4s15.5048

Also Known As

  • K
  • element 19
  • 19K

Translations

  • Italianpotassio
  • Norwegian Bokmålkalium
  • Frenchpotassium
  • GermanKalium
  • Dutchkalium
  • Spanishpotasio
  • Chinese (Traditional)
  • Afrikaanskalium
  • Amharicፖታሺየም
  • AragonesePotasio
  • Arabicبوتاسيوم
  • AsturianPotasiu
  • AzerbaijaniKalium
  • BashkirКалий
  • BelarusianКалій
  • Bulgarianкалий
  • Banglaপটাশিয়াম
  • BretonPotasiom
  • Bosniankalij
  • Catalanpotassi
  • CherokeeᏉᏔᏏᎥᎻ
  • CorsicanPotassiu
  • Czechdraslík
  • ChuvashКали
  • WelshPotasiwm
  • Danishkalium
  • Divehiޕޮޓޭސިއަމް
  • Greekκάλιο
  • Esperantokalio
  • EstonianKaalium
  • Basquepotasio
  • Persianپتاسیم
  • Finnishkalium
  • Northern FrisianKaalium
  • FriulianPotassi
  • IrishPotaisiam
  • GalicianPotasio
  • Gujaratiપોટેશિયમ
  • ManxPotashum
  • Hakka ChineseKap
  • HawaiianPotasiuma
  • Hebrewאשלגן
  • Hindiपोटैशिय
  • Fiji HindiPotassium
  • Croatiankalij
  • Haitian CreolePotasyòm
  • Hungariankálium
  • Armenianկալիում
  • Interlinguapotassium
  • Indonesiankalium
  • Idokalio
  • Icelandickalín
  • Japaneseカリウム
  • Lojbansodnrkali
  • JavaneseKalium
  • Georgianკალიუმი
  • KazakhКалий
  • Kannadaಪೊಟ್ಯಾಶಿಯಮ್
  • Korean칼륨
  • KurdishQelye
  • KomiКалий
  • Latinkalium
  • LuxembourgishKalium
  • LigurianPotassio
  • LingalaPotasu
  • LithuanianKalis
  • Latviankālijs
  • Māorikonurehu
  • Macedonianкалиум
  • Malayalamപൊട്ടാസ്യം
  • Marathiपलाश
  • Western MariКалий
  • Malaykalium
  • Burmeseပိုတက်ဆီယမ်
  • Low GermanKalium
  • Nepaliपोटासियम
  • Norwegian Nynorskkalium
  • Novialkalium
  • OccitanPotassi
  • Punjabiਪੋਟਾਸ਼ਿਅਮ
  • Polishpotas
  • Western Panjabiپوٹاشیم
  • Portuguesepotássio
  • QuechuaKalyu
  • Romanianpotasiu
  • Russianкалий
  • Sanskritपोटासियम्
  • YakutКалиум
  • Sicilianputassiu
  • Serbo-CroatianKalij
  • Sinhalaපොටෑසියම්
  • Slovakdraslík
  • Sloveniankalij
  • AlbanianKaliumi
  • Serbianкалијум
  • Saterland FrisianKalium
  • Swedishkalium
  • SwahiliKali
  • Tamilபொற்றாசியம்
  • Teluguపొటాషియం
  • TajikКалий
  • Thaiโพแทสเซียม
  • TagalogPotasyo
  • TurkishPotasyum
  • Tatarкалий
  • Uyghurكالىي
  • Ukrainianкалій
  • Urduاُشنانصر
  • UzbekKaliy
  • VepsKalii
  • Vietnamesekali
  • West FlemishKalium
  • WalloonPotassiom
  • WarayPotasyo
  • KalmykКалион
  • Yiddishקאליום
  • YorubaPotassium
  • ZhuangGyaz
  • Chinese
  • English (Canada)Potassium
  • English (United Kingdom)potassium
  • German (Switzerland)Kalium
  • Portuguese (Brazil)potássio
  • Cantonese
  • Belarusian (Taraskievica orthography)каль
  • CebuanoPotasio
  • Central Kurdishپۆتاسیۆم
  • Newariपोटासियम
  • Odiaପୋଟାସିଅମ
  • PiedmontesePotassi
  • KikuyuPotasium
  • Scotspotassium
  • Chinese (Hong Kong SAR China)
  • Chinese (China)
  • Literary Chinese
  • Min Nan ChineseKalium
  • LombardPotasse
  • SomaliBotashiyaam
  • AromanianKaliu
  • LimburgishKalium
  • KyrgyzКалий
  • cdoGák
  • FaroeseKalium
  • Scottish GaelicPotasium
  • Maltesepotassju
  • Gan Chinese
  • Bhojpuriपोटैशियम
  • Mongolianкали
  • SundaneseKalium
  • Tibetanདུག་སེལ།
  • oloKalii
  • azbپوتاسیوم
  • Lingua Franca Novapotasio
  • Tatar (Cyrillic)калий
  • Wu Chinese
  • kbpPɔtasɩyɔm
  • Chinese (Taiwan)
  • ExtremaduranPotasiu
  • Chinese (Simplified)
  • SardinianPudassa
  • Moroccan Arabicپوطاسيوم
  • Egyptian Arabicبوتاسيوم
  • BikolPotasyo
  • lldPotassie
  • Manipuriꯄꯣꯇꯥꯁꯤꯌꯝ
  • CornishPotassiom
  • BalinesePotasium
  • ZuluPotassium nitrate
  • Malay (Arabic)کاليوم
  • Paliपोटासियम
  • Korean (North Korea)칼리움
  • Pashtoپوتاشیم