Cs Cesium – Element Information, Facts, Properties, Trends,Uses, Comparison with other elements

55
Cs
Cesium

Cesium

Element 55 of Periodic table is Cesium with atomic number 55, atomic weight 132.90545. Cesium, symbol Cs, has a Body Centered Cubic structure and Silver color. Cesium is a alkali metal element. Trivial name of Cesium is alkali metals*. Know everything about Cesium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.

55 Cs - Cesium | SchoolMyKids

Caesium or cesium is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28 °C (82 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium is an alkali metal and has physical and chemical properties similar to those of rubidium and potassium.

How to Locate Cesium on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 55 to find Cesium on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Cesium on periodic table look for cross section of group 1 and period 6 in the modern periodic table.

Table of Contents

Cesium History

The element Cesium was discovered by Robert Bunsen in year 1860 in Germany . Cesium derived its name from the Latin caesius, meaning 'sky blue'

Cesium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Cesium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.

  Ppb by weight (1ppb =10^-7 %)
Abundance in Universe 8×10-8%
Abundance in Sun 8×10-7%
Abundance in Meteorites 1.4e-07
Abundance in Earth's Crust 1.9e-06
Abundance in Oceans 5×10-8%
Abundance in Humans 2×10-6%

Crystal Structure of Cesium

The solid state structure of Cesium is Body Centered Cubic.

The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.

Unit Cell Parameters

The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)

a b c
614.1 614.1 614.1 pm

and the angles between them Lattice Angles (alpha, beta and gamma).

alpha beta gamma
π/2 π/2 π/2

The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.

The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.

Space Group Name Im_ 3m 55 Cs Cesium - Crystal Structure | SchoolMyKids
Space Group Number 229
Crystal Structure Body Centered Cubic

Cesium Atomic and Orbital Properties

Cesium atoms have 55 electrons and the electronic shell structure is [2, 8, 18, 18, 8, 1] with Atomic Term Symbol (Quantum Numbers) 2S1/2.

Atomic Number 55
Number of Electrons (with no charge) 55
Number of Protons 55
Mass Number 133
Number of Neutrons 78
Shell structure (Electrons per energy level) [2, 8, 18, 18, 8, 1]
Electron Configuration [Xe] 6s1
Valence Electrons 6s1
Oxidation State -1
1
Atomic Term Symbol (Quantum Numbers) 2S1/2

Shell Structure of Cesium - Electrons per energy level

55 Cs Cesium - Electron Shell Structure | SchoolMyKids
n s p d f
1 K 2
2 L 2 6
3 M 2 6 10
4 N 2 6 10
5 O 2 6
6 P 1

Ground State Electronic Configuration of Cesium - neutral Cesium atom

The ground state electronic configuration of Neutral Cesium atom is [Xe] 6s1. The portion of Cesium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Xe]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used.This is important as it is the Valence electrons 6s1, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Cesium

Complete ground state electronic configuration for the Cesium atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s1

Atomic Structure of Cesium

Cesium atomic radius is 298 pm, while it's covalent radius is 225 pm.

Atomic Radius

298 pm (2.98 Å)

Atomic Volume 70.7320117084 cm3
Covalent Radius 225 pm (2.25 Å)
Van der Waals Radius N/A
Neutron Cross Section 29 σa/barns

Atomic Spectrum of Cesium

Atomic Spectrum of Cesium | SchoolMyKids

Cesium Chemical Properties: Cesium Ionization Energies and electron affinity

The electron affinity of Cesium is 45.5 kJ/mol

Valence 1
Electronegativity 0.79
ElectronAffinity 45.5 kJ/mol

Ionization Energy of Cesium

Refer to table below for Ionization energies of Cesium

Ionization energy number Enthalpy - kJ/mol
1 375.7
2 2234.3
3 3.4×103

Cesium Physical Properties

Refer to below table for Cesium Physical Properties

Density 1.879 g/cm3
Molar Volume 70.7320117084 cm3

Elastic Properties

Young Modulus 1.7 GPa
Shear Modulus N/A
Bulk Modulus 1.6 GPa
Poisson Ratio N/A

Hardness of Cesium - Tests to Measure of Hardness of Element

Mohs Hardness 0.2 MPa
Vickers Hardness N/A
Brinell Hardness 0.14 MPa

Cesium Electrical Properties

Cesium is Conductor of electricity. Refer to table below for the Electrical properties of Cesium

Electrical Conductivity 5×106 S/m
Resistivity 2×10-7 m Ω
Superconducting Point N/A

Cesium Heat and Conduction Properties

Thermal Conductivity 36 W/(m K)
Thermal Expansion N/A

Cesium Magnetic Properties

Magnetic Type Paramagnetic
Curie Point N/A
Mass Magnetic Susceptibility 2.8×10-9
Molar Magnetic Susceptibility 3.72×10-10
Volume Magnetic Susceptibility 5.26×10-6

Optical Properties of Cesium

Refractive Index N/A

Acoustic Properties of Cesium

Speed of Sound N/A

Cesium Thermal Properties - Enthalpies and thermodynamics

Refer to table below for Thermal properties of Cesium

Melting Point 301.59 K (28.44 °C)
Boiling Point 944 K (671 °C)
Critical Temperature 1938 K
Superconducting Point N/A

Enthalpies of Cesium

Heat of Fusion 2.09 kJ/mol
Heat of Vaporization 65 kJ/mol
Heat of Combustion N/A

Cesium Isotopes - Nuclear Properties of Cesium

Isotopes of rhodium. Naturally occurring Cesium has 1 stable isotope - 133Cs.

Isotope Isotope Mass % Abundance T half Decay Mode
112Cs  
113Cs  
114Cs  
115Cs  
116Cs  
117Cs  
118Cs  
119Cs  
120Cs  
121Cs  
122Cs  
123Cs  
124Cs  
125Cs  
126Cs  
127Cs  
128Cs  
129Cs  
130Cs  
131Cs  
132Cs  
133Cs   100% Stable N/A
134Cs  
135Cs  
136Cs  
137Cs  
138Cs  
139Cs  
140Cs  
141Cs  
142Cs  
143Cs  
144Cs  
145Cs  
146Cs  
147Cs  
148Cs  
149Cs  
150Cs  
151Cs  

Regulatory and Health - Health and Safety Parameters and Guidelines

CAS Number CAS7440-46-2
RTECS Number RTECSFK9225000
DOT Hazard Class 4.3
DOT Numbers 1407
EU Number N/A
NFPA Fire Rating N/A
NFPA Hazards Water Reactive
NFPA Health Rating N/A
NFPA Reactivity Rating N/A
Autoignition Point N/A
Flashpoint N/A

Database Search

List of unique identifiers to search the element in various chemical registry databases

Database Identifier number
CAS Number - Chemical Abstracts Service (CAS) CAS7440-46-2
CID Number CID5354618
Gmelin Number N/A
NSC Number N/A
RTECS Number RTECSFK9225000

List of Elements
1 H - Hydrogen
2 He - Helium
3 Li - Lithium
4 Be - Beryllium
5 B - Boron
6 C - Carbon
7 N - Nitrogen
8 O - Oxygen
9 F - Fluorine
10 Ne - Neon
11 Na - Sodium
12 Mg - Magnesium
13 Al - Aluminium
14 Si - Silicon
15 P - Phosphorus
16 S - Sulfur
17 Cl - Chlorine
18 Ar - Argon
19 K - Potassium
20 Ca - Calcium
21 Sc - Scandium
22 Ti - Titanium
23 V - Vanadium
24 Cr - Chromium
25 Mn - Manganese
26 Fe - Iron
27 Co - Cobalt
28 Ni - Nickel
29 Cu - Copper
30 Zn - Zinc
31 Ga - Gallium
32 Ge - Germanium
33 As - Arsenic
34 Se - Selenium
35 Br - Bromine
36 Kr - Krypton
37 Rb - Rubidium
38 Sr - Strontium
39 Y - Yttrium
40 Zr - Zirconium
41 Nb - Niobium
42 Mo - Molybdenum
43 Tc - Technetium
44 Ru - Ruthenium
45 Rh - Rhodium
46 Pd - Palladium
47 Ag - Silver
48 Cd - Cadmium
49 In - Indium
50 Sn - Tin
51 Sb - Antimony
52 Te - Tellurium
53 I - Iodine
54 Xe - Xenon
55 Cs - Cesium
56 Ba - Barium
57 La - Lanthanum
58 Ce - Cerium
59 Pr - Praseodymium
60 Nd - Neodymium
61 Pm - Promethium
62 Sm - Samarium
63 Eu - Europium
64 Gd - Gadolinium
65 Tb - Terbium
66 Dy - Dysprosium
67 Ho - Holmium
68 Er - Erbium
69 Tm - Thulium
70 Yb - Ytterbium
71 Lu - Lutetium
72 Hf - Hafnium
73 Ta - Tantalum
74 W - Tungsten
75 Re - Rhenium
76 Os - Osmium
77 Ir - Iridium
78 Pt - Platinum
79 Au - Gold
80 Hg - Mercury
81 Tl - Thallium
82 Pb - Lead
83 Bi - Bismuth
84 Po - Polonium
85 At - Astatine
86 Rn - Radon
87 Fr - Francium
88 Ra - Radium
89 Ac - Actinium
90 Th - Thorium
91 Pa - Protactinium
92 U - Uranium
93 Np - Neptunium
94 Pu - Plutonium
95 Am - Americium
96 Cm - Curium
97 Bk - Berkelium
98 Cf - Californium
99 Es - Einsteinium
100 Fm - Fermium
101 Md - Mendelevium
102 No - Nobelium
103 Lr - Lawrencium
104 Rf - Rutherfordium
105 Db - Dubnium
106 Sg - Seaborgium
107 Bh - Bohrium
108 Hs - Hassium
109 Mt - Meitnerium
110 Ds - Darmstadtium
111 Rg - Roentgenium
112 Cn - Copernicium
113 Nh - Nihonium
114 Fl - Flerovium
115 Mc - Moscovium
116 Lv - Livermorium
117 Ts - Tennessine
118 Og - Oganesson
Metalloid
Nonmetals
Other Nonmetals
Halogens Noble Gas
Metals
Alkali Metals Alkaline Earth Metals
Transition Metals Post-Transition Metals
Lanthanide Actinide