Bromine Rubidium

Krypton (Kr)

From Wikipedia, the free encyclopediaKrypton (from Greek:κρυπτός kryptos "the hidden one") is a chemical element with symbol Kr and atomic number 36. It is a member of group 18 (noble gases) elements. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere, is isolated by fractionally distilling liquefied air, and is often used with other rare gases in fluorescent lamps.

Krypton in the periodic table

Symbol

Atomic number

Group

Period

Block

Element category

Noble Gas

Physical properties

Phase at STP

Gas

Density

3.749 g/cm³

Atomic weight

83.7982 u

Melting point

115.78 K
-157.37 °C
-251.266 °F

Boiling point

119.93 K
-153.22 °C
-243.796 °F

Atomic properties

Electronegativity (Pauling Scale)

Electron affinity

-96 kJ/mol

Oxidation states

0, +1, +2
(rarely more than 0; oxide is unknown)

Ionization energies

1	1350.8 kJ/mol
2	2350.4 kJ/mol
3	3565 kJ/mol
4	5070 kJ/mol
5	6240 kJ/mol
6	7570 kJ/mol
7	10710 kJ/mol
8	12138 kJ/mol
9	22274 kJ/mol
10	25880 kJ/mol
11	29700 kJ/mol
12	33800 kJ/mol
13	37700 kJ/mol
14	43100 kJ/mol
15	47500 kJ/mol
16	52200 kJ/mol
17	57100 kJ/mol
18	61800 kJ/mol
19	75800 kJ/mol
20	80400 kJ/mol
21	85300 kJ/mol
22	90400 kJ/mol
23	96300 kJ/mol
24	101400 kJ/mol
25	111100 kJ/mol
26	116290 kJ/mol
27	282500 kJ/mol
28	296200 kJ/mol
29	311400 kJ/mol
30	326200 kJ/mol

Electron configuration

Elektronkonfiguration (shorthand)

[Ar] 3d¹⁰ 4s² 4p⁶

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶

Electrons per shell

2, 8, 18, 8

History

Discovered

1898

Discovered by

William Ramsay
Morris Travers