Selenium

Element 34 of Periodic table is Selenium with atomic number 34, atomic weight 78.96. Selenium, symbol Se, has actually a Simple Monoclinic structure and also Gray color. Selenium is a various other nonmetal facet. Trivial name of Selenium is chalcogens*. Know whatever around Selenium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and also Crystal Structure.


*

Selenium is a chemical element through symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between those of its routine table column-nearby chalcogen aspects sulfur and also tellurium. It rarely occurs in its elepsychological state in nature, or as pure ore compounds.

You are watching: Number of valence electrons in se


Selenium Facts

Read essential indevelopment and also facts about facet Selenium

Name Selenium
Atomic Number 34
Atomic Symbol Se
Atomic Weight 78.96
Phase Solid
Color Gray
Classification other nonmetal
Group in Periodic Table 16
Group Name oxygen family members
Period in Periodic Table 4
Block in Periodic Table p-block
Electronic Configuration 3d10 4s2 4p4
Melting Point 221 °C
Boiling Point 685 °C
Electronic Shell Structure <2, 8, 18, 6>
CAS Number CAS7782-49-2

Neighborhood
15
P
16
S
17
Cl
33
As
34
Se
35
Br
51
Sb
52
Te
53
I
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
1
1
H
2
He
2
3
Li
4
Be
5
B
6
C
7
N
8
O
9
F
10
Ne
3
11
Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
4
19
K
20
Ca
21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
28
Ni
29
Cu
30
Zn
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
5
37
Rb
38
Sr
39
Y
40
Zr
41
Nb
42
Mo
43
Tc
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
54
Xe
6
55
Cs
56
Ba
72
Hf
73
Ta
74
W
75
Re
76
Os
77
Ir
78
Pt
79
Au
80
Hg
81
Tl
82
Pb
83
Bi
84
Po
85
At
86
Rn
7
87
Fr
88
Ra
104
Rf
105
Db
106
Sg
107
Bh
108
Hs
109
Mt
110
Ds
111
Rg
112
Cn
113
Nh
114
Fl
115
Mc
116
Lv
117
Ts
118
Og
Lanthanides
57
La
58
Ce
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
Actinide
89
Ac
90
Th
91
Pa
92
U
93
Np
94
Pu
95
Am
96
Cm
97
Bk
98
Cf
99
Es
100
Fm
101
Md
102
No
103
Lr

Explore our interenergetic routine table


How to Locate Selenium on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is exact same as variety of electrons. The atomic number increases from left to ideal. Periodic table starts at top left ( Atomic number 1) and also ends at bottom ideal (atomic number 118). Thus you can directly look for atomic number 34 to discover Selenium on periodic table.

Another way to check out periodic table and also locate an aspect is by utilizing team number (column) and also period number (row). To situate Selenium on routine table look for cross area of team 16 and period 4 in the modern regular table.

Explore Interenergetic Periodic Table to Understand also and Find Out Cool Trends

Table of Contents


History
Abundance
Physical Properties
Thermal Properties
Crystal Structure
Atomic & Orbital Properties
Chemical Properties
Isotopes
Health and also Safety Parameters and also Guidelines
Databases
Compare Selenium through various other elements

Selenium History

The aspect Selenium was found by Jöns Jakob Berzelius in year 1817 in Sweden . Selenium obtained its name from the Greek selene, meaning "moon"

Selenium Presence: Abundance in Nature and also Around Us

The table below reflects the abundance of Selenium in Universe, Sun, Meteorites, Earth"s Crust, Oceans and Person Body.

Ppb by weight (1ppb =10^-7 %)
Abundance in Universe 3×10-6%
Abundance in Sun N/A
Abundance in Meteorites 1.3e-05
Abundance in Earth"s Crust 5×10-6%
Abundance in Oceans 4.5×10-8%
Abundance in Humans 5×10-6%

Crystal Structure of Selenium

The solid state framework of Selenium is Simple Monoclinic.

The Crystal framework deserve to be described in terms of its unit Cell. The unit Cells repeats itself in 3 dimensional space to develop the framework.

Unit Cell Parameters

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

a b c
905.4 908.3 1160.1 pm

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

alpha beta gamma
π/2 1.58493 π/2

The positions of the atoms inside the unit cell are defined by the set of atomic positions ( xi, yi, zi) measured from a recommendation lattice allude.

The symmetry properties of the crystal are defined by the concept of room teams. All feasible symmetric arrangements of pshort articles in three-dimensional space are described by the 230 space groups (219 distinctive types, or 230 if chiral duplicates are taken into consideration distinct.

Void Group Name P121/c1
*
Gap Group Number 14
Crystal Structure Simple Monoclinic

Selenium Atomic and also Orbital Properties

Selenium atoms have 34 electrons and also the electronic shell framework is <2, 8, 18, 6> via Atomic Term Symbol (Quantum Numbers) 3P2.


Atomic Number 34
Number of Electrons (with no charge) 34
Number of Protons 34
Mass Number 79
Number of Neutrons 45
Shell framework (Electrons per energy level) <2, 8, 18, 6>
Electron Configuration 3d10 4s2 4p4
Valence Electrons 4s2 4p4
Oxidation State -2;-1 1;2;3;4;5;6
Atomic Term Symbol (Quantum Numbers) 3P2

Covering Structure of Selenium - Electrons per power level


*

Ground State Electronic Configuration of Selenium - neutral Selenium atom

The ground state digital configuration of Neutral Selenium atom is 3d10 4s2 4p4. The portion of Selenium configuration that is tantamount to the noble gas of the preceding period, is abbreviated as . For atoms via many kind of electrons, this notation can come to be lengthy and also so an abbreviated notation is used.This is vital as it is the Valence electrons 3d10 4s2 4p4, electrons in the outerthe majority of shell that identify the chemical properties of the facet.

See more: How Many Ribs Does A Man And Woman Have More Ribs Than Men, How Many Ribs Does A Man Have

Unabbreviated digital configuration of neutral Selenium

Complete ground state electronic configuration for the Selenium atom, Unabbreviated digital configuration

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p4

Atomic Structure of Selenium

Selenium atomic radius is 103 pm, while it"s covalent radius is 116 pm.

Atomic Radius

103 pm (1.03 Å)

Atomic Volume 16.3851421457 cm3
Covalent Radius 116 pm (1.16 Å)
Van der Waals Radius 190 pm
Neutron Cross Section 11.7 σa/barns

Atomic Spectrum of Selenium

*

Selenium Chemical Properties: Selenium Ionization Energies and electron affinity

The electron affinity of Selenium is 195 kJ/mol

Valence 6
Electronegativity 2.55
ElectronAffinity 195 kJ/mol

Ionization Energy of Selenium

Refer to table below for Ionization energies of Selenium

Ionization power number Enthalpy - kJ/mol
1 941
2 2045
3 2973.7
4 4144
5 6590
6 7880
7 14990

Selenium Physical Properties

Refer to below table for Selenium Physical Properties

Density 4.819 g/cm3
Molar Volume 16.3851421457 cm3

Elastic Properties

Young Modulus 10 GPa
Shear Modulus 3.7 GPa
Bulk Modulus 8.3 GPa
Poisson Ratio 0.33

Hardness of Selenium - Tests to Meacertain of Hardness of Element

Mohs Hardness 2 MPa
Vickers Hardness N/A
Brinell Hardness 736 MPa

Selenium Electrical Properties

Selenium is N/A of electricity. Refer to table below for the Electrical properties of Selenium

Electrical Conductivity N/A
Resistivity N/A
Superconducting Point N/A

Selenium Heat and also Conduction Properties

Thermal Conductivity 0.52 W/(m K)
Thermal Expansion N/A

Selenium Magnetic Properties

Magnetic Type Diamagnetic
Curie Point N/A
Mass Magnetic Susceptibility -4×10-9
Molar Magnetic Susceptibility -3.16×10-10
Volume Magnetic Susceptibility -1.93e-05

Optical Properties of Selenium

Refrenergetic Index 1.000895

Acoustic Properties of Selenium

Speed of Sound 3350 m/s

Selenium Thermal Properties - Enthalpies and also thermodynamics

Refer to table listed below for Thermal properties of Selenium

Melting Point 494 K (221 °C)
Boiling Point 958 K (685 °C)
Critical Temperature 1766 K
Superconducting Point N/A

Enthalpies of Selenium

Heat of Fusion 5.4 kJ/mol
Heat of Vaporization 26 kJ/mol
Heat of Combustion "N/A", "N/A", "N/A" J/(kg K)

Selenium Isotopes - Nuclear Properties of Selenium

Isotopes of rhodium. Naturally developing Selenium has 5 stable isotope - 74Se, 76Se, 77Se, 78Se, 80Se.


Isotope Isotope Mass % Abundance T half Decay Mode
65Se
66Se
67Se
68Se
69Se
70Se
71Se
72Se
73Se
74Se 0.89% Stable N/A
75Se
76Se 9.37% Stable N/A
77Se 7.63% Stable N/A
78Se 23.77% Stable N/A
79Se
80Se 49.61% Stable N/A
81Se
82Se 8.73%
83Se
84Se
85Se
86Se
87Se
88Se
89Se
90Se
91Se
92Se
93Se
94Se

Regulatory and Health - Health and also Safety Parameters and also Guidelines

CAS Number CAS7782-49-2
RTECS Number N/A, RTECSVS7700000, N/A
DOT Hazard Class N/A, 6.1, N/A
DOT Numbers "N/A", 2658, "N/A"
EU Number N/A, N/A, N/A
NFPA Fire Rating N/A, 0, N/A
NFPA Hazards N/ A, N/ A, N/ A
NFPA Health Rating N/A, 2, N/A
NFPA Reactivity Rating N/A, 0, N/A
Autoignition Point N/A
Flashpoint N/A

Database Search

List of distinctive identifiers to search the element in miscellaneous chemical regisattempt databases

Database Identifier number
CAS Number - Chemical Abstracts Service (CAS) CAS7782-49-2
CID Number CID6326970, CID6326970, CID139346
Gmelin Number N/A, N/A, N/A
NSC Number N/A, N/A, N/A
RTECS Number N/A, RTECSVS7700000, N/A

Compare Selenium through all Group 16 elements

Selenium vs Oxygen Selenium vs Sulfur Selenium vs Tellurium Selenium vs Polonium Selenium vs Livermorium

Compare Selenium with all various other nonmetal elements

Selenium vs Hydrogen Selenium vs Carbon Selenium vs Nitrogen Selenium vs Oxygen Selenium vs Phosphorus Selenium vs Sulfur