POTASSIUM, K (19)

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Elemental Tile
Potassium from Potash
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POTASSIUM

K (19)

pəˈtæsiəm

PHONETICS

Potassium, also known as kalium, is the second least dense metal after lithium. It is a soft solid that has a low melting point and can easily be cut with a knife and is silvery in appearance, yet begins to tarnish toward grey, immediately after being exposed to air.

ELEMENT BRIEF

1807 by Sir Humphrey Davy, England.

DISCOVERY

English, 'potash' and Arabic 'qali' meaning alkali (symbol K from Latin 'kalium').

ETYMOLOGY

Potassium

ELEMENT

K

SYMBOL

19

ATOMIC NUMBER

7440-09-7

CAS NUMBER
element

ELEMENTAL SPECTRUM


Silver

ELEMENTAL COLOUR


-

REFRACTIVE INDEX


-

POISSON RATIO


45.676 cm³

MOLAR VOLUME


363.00k Pa, 3.582'5 Atm

BRINELL HARDNESS


0.40

MOHS HARDNESS


-

VICKERS HARDNESS


2,000 m/s, Mach 5.830'9

SPEED OF SOUND


3.10G Pa, 30.594'6k Atm

BULK MODULUS


1.30G Pa, 12.830'0k Atm

SHEAR MODULUS


-

YOUNG MODULUS


ALLOTROPES

NONE

336.53 K, 63.38 °C

MELTING POINT


1,032.15 K, 759.00 °C

BOILING POINT


713.15 K, 440.00 °C

AUTOMATIC IGNITION


-

FLASHPOINT


2,223.00 K, 1,949.85 °C

CRITICAL TEMPERATURE


16.00M Pa, 158 Atm

CRITICAL PRESSURE


100.000'000 W/(m K)

THERMAL CONDUCTIVITY


-

THERMAL EXPANSION


757.00 J/(kg K)

SPECIFIC HEAT


2.330 kJ/mol

HEAT FUSION


76.900 kJ/mol

HEAT VAPORISATION


182.000 J/(kg K)

HEAT COMBUSTION


-

CURIE POINT


-

NEEL POINT


-

ADIABATIC INDEX


Solid

PHASE

Conductor

ELECTRICAL TYPE


14.00M S/m

CONDUCTIVITY


70.00n Ω.m

RESISTIVITY


-

SUPERCONDUCTING POINT


Diamagnetic

MAGNETIC TYPE


0.000'000'006'7

MASS SUSCEPTIBILITY


0.000'000'000'262'00

MOLAR SUSCEPTIBILITY


0.000'005'740'00

VOLUME SUSCEPTIBILITY

Alkali Metal

CLASSIFICATION


39.098'301'1

ATOMIC WEIGHT


243 pm

ATOMIC RADIUS


196 pm

COVALENT RADIUS SINGLE BOND


193 pm

COVALENT RADIUS DOUBLE BOND


-

COVALENT RADIUS TRIPLE BOND


275 pm

VAN DER WAALS RADIUS


[Ar]4s¹

ELECTRON CONFIGURATION


Cubic, Body-centred

CRYSTAL STRUCTURE


0.856'00 g/cm³

DENSITY AS SOLID


0.828'00 g/cm³

DENSITY AS LIQUID


-

DENSITY AS GAS


lm_3m

SPACE GROUP NAME


229

SPACE GROUP NUMBER


π/2, π/2 π/2

LATTICE ANGLES


532.8, 532.8 532.8 pm

LATTICE CONSTANTS

1

VALENCE


0.82

ELECTRONEGATIVITY


48.38 kJ/mol

ELECTRON AFFINITY


IONISATION ENERGY

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0.000'3 %

UNIVERSE


0.07 %

METEORITES


0.000'4 %

SUN


1.5 %

EARTH CRUST


0.042 %

OCEANS


0.2 %

HUMANS

Stable

HALF LIFE


Stable

LIFETIME


4s¹ = 4, 0, 0, +1/2

QUANTUM NUMBERS


1.960'00 b σs

NEUTRON CROSS SECTION


2.100'00 b σa

NEUTRON MASS ABSORPTION


STABLE ISOTOPES

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UNSTABLE ISOTOPES

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ISOTOPIC CHAIN

CENTRALDATACORE

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