Καίσιο

55
Cs
Ομάδα
1
Περίοδος
6
Τομέας
s
Πρωτονίων
Electrons
Νετρονίων
55
55
78
General Properties
Ατομικός Αριθμός
55
Ατομικό βάρος
132,9054519
Mass Number
133
Κατηγορία
Αλκάλια
Χρώμα
Silver
Radioactive
Ναι
From the Latin word caesius, sky blue
Κρυσταλλικό σύστημα
Body Centered Cubic
Ιστορία
Robert Bunsen and Gustav Kirchhoff were the first to suggest finding cesium in 1860 by spectrum analysis.

They discovered cesium by its two blue emission lines in a sample of Dürkheim mineral water.

The pure metal was eventually isolated by the German chemist Carl Setterberg while working on his doctorate with Kekulé and Bunsen.
Electrons per shell
2, 8, 18, 18, 8, 1
Ηλεκτρονική διαμόρφωση
[Xe] 6s1
Cs
Cesium was the first element discovered using a spectroscope
Physical Properties
Phase
Στερεά
Πυκνότητα
1,873 g/cm3
Σημείο τήξης
301,59 K | 28,44 °C | 83,19 °F
Σημείο βρασμού
944,15 K | 671 °C | 1239,8 °F
Heat of Fusion
2,09 kJ/mol
Heat of Vaporization
65 kJ/mol
Ειδική θερμοχωρητικότητα
0,242 J/g·K
Abundance in Earth's crust
0,00019%
Abundance in Universe
8×10-8%
Cesium
Image Credits: Wikimedia Commons (Dnn87)
Cesium metal sample from the Dennis s.k collection
CAS Number
7440-46-2
PubChem CID Number
5354618
Atomic Properties
Ατομική ακτίνα
265 pm
Ομοιοπολική ακτίνα
244 pm
Ηλεκτραρνητικότητα
0,79 (Κλίμακα Pauling)
Ionization Potential
3,8939 eV
Atomic Volume
71,07 cm3/mol
Θερμική αγωγιμότητα
0,359 W/cm·K
Oxidation States
-1, 1
Applications
The radioactive isotope cesium-137 has a half-life of about 30 years and is used in medical applications, industrial gauges, and hydrology.

Cesium is also used in photoelectric cells and as a catalyst in the hydrogenation of organic compounds.

Cesium vapor thermionic generators are low-power devices that convert heat energy to electrical energy.
Cesium compounds are considered to be mildly toxic
Ισότοπα
Stable Isotopes
133Cs
Unstable Isotopes
112Cs, 113Cs, 114Cs, 115Cs, 116Cs, 117Cs, 118Cs, 119Cs, 120Cs, 121Cs, 122Cs, 123Cs, 124Cs, 125Cs, 126Cs, 127Cs, 128Cs, 129Cs, 130Cs, 131Cs, 132Cs, 134Cs, 135Cs, 136Cs, 137Cs, 138Cs, 139Cs, 140Cs, 141Cs, 142Cs, 143Cs, 144Cs, 145Cs, 146Cs, 147Cs, 148Cs, 149Cs, 150Cs, 151Cs