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

SymbolKr
Atomic number36
Group18
Period4
Blockp
Element categoryNoble Gas

Physical properties

Phase at STPGas
Density3.749 g/cm3
Atomic weight83.7982 u
Melting point115.78 K
-157.37 °C
-251.266 °F
Boiling point119.93 K
-153.22 °C
-243.796 °F

Atomära egenskaper

Electronegativity (Pauling Scale)3
Electron affinity-96 kJ/mol
Ionization energies
11350.8 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

Electron configuration1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6
Electrons per shell2, 8, 18, 8

History

Discovered1898
Discovered byWilliam Ramsay
Morris Travers