Cesyo

Caesium
55Cs
Rb ↑ Cs ↓ Fr Periodic table xenon ← caesium → barium
Appearance
silvery gold
General properties
Name, simbolo, kaiphan	caesium, Cs, 55
Pronunciation	Plantilya:IPAc-en Plantilya:Respell
Element category	puthaw
Group, period, block	1, 6, s
Standard atomic weight	132.9054519(2)
Electron configuration	[Xe] 6s1 2, 8, 18, 18, 8, 1
History
Discovery	Robert Bunsen and Gustav Kirchhoff (1860)
First isolation	Carl Setterberg (1882)
Physical properties
Phase	magahi
Density (near r.t.)	1.93 g·cm−3
Liquid density at m.p.	1.843 g·cm−3
Melting point	301.59 K, 28.44 °C, 83.19 °F
Boiling point	944 K, 671 °C, 1240 °F
Critical point	1938 K, 9.4 MPa
Heat of fusion	2.09 kJ·mol−1
Heat of vaporization	63.9 kJ·mol−1
Molar heat capacity	32.210 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 418 469 534 623 750 940
Atomic properties
Oxidation states	1 (strongly basic oxide)
Electronegativity	0.79 (Pauling scale)
Ionization energies	1st: 375.7 kJ·mol−1
	2nd: 2234.3 kJ·mol−1
	3rd: 3400 kJ·mol−1
Atomic radius	265 pm
Covalent radius	244±11 pm
Van der Waals radius	343 pm
Miscellanea
Crystal structure	body-centered cubic
Magnetic ordering	paramagnetic
Electrical resistivity	(20 °C) 205 nΩ·m
Thermal conductivity	35.9 W·m−1·K−1
Thermal expansion	(25 °C) 97 µm·m−1·K−1
Young's modulus	1.7 GPa
Bulk modulus	1.6 GPa
Mohs hardness	0.2
Brinell hardness	0.14 MPa
CAS registry number	7440-46-2
Most stable isotopes
Main article: Isotopes of caesium
iso NA half-life DM DE (MeV) DP 133Cs 100% 133Cs is stable with 78 neutrons 134Cs syn 2.0648 y ε 1.229 134Xe β− 2.059 134Ba 135Cs trace 2.3×106 y β− 0.269 135Ba 137Cs trace 30.17 y β− 1.174 137Ba

Ang cesyo (Iningles caesium) mao ang elementong kimiko sa talaang peryodiko nga may simbolo nga Cs ug kaiphan nga atomik 55. Ang cesyo mao ang puthaw.

Galeriya sa hulagway

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