Atomic number:36

Group numbers:18

Period:4

Electronic configuration:[Ar] 3d¹⁰ 4s² 4p⁶

Formal oxidation number:0

Electronegativities:-

Atomic radius / pm:202

Relative atomic mass:83.798 ± 0.002

 

Krypton was discovered by Sir William Ramsay and Morris William Travers (GB) in 1898. The origin of the name comes from the Greek word kryptos meaning hidden. It is a colourless, odourless rare noble gas that reacts only with fluorine. Krypton is obtained from production of liquid air. Krypton is used in lighting products. It is used as inert filler-gas in incandescent bulbs and some is mixed with argon in fluorescent lamps. The most important use is in flashing stroboscopic lamps that outline airport runways.

Density / g dm^-3:2823 (solid, m.p.)

 2413 (liquid, b.p.)

 3.7493 (gas, 273 K)

Molar volume / cm³mol^-1:29.68 (solid, m.p.)

 34.73 (liquid, b.p.)

 22350.84 (gas, 273 K)

Electrical resistivity / μΩcm:- (20 °C)

Thermal conductivity / W m^-1K^-1:0.0095

Melting point / °C:-157.36

Boiling point / °C:-153.22

Heat of fusion / kJ mol^-1:1.64

Heat of vaporization / kJ mol^-1:9.05

Heat of atomization / kJ mol^-1:0

1st ionization energy / kJ mol^-1:1350.77

2nd ionization energy / kJ mol^-1:2350.39

3rd ionization energy / kJ mol^-1:3565.16

in the atmosphere / ppm:1.14

in the Earth's crust / ppm:0.00001

in the oceans / ppm:0.0003