Element 17 of Periodic table is Chlorine with atomic number 17, atomic weight 35.453. Chlorine, symbol Cl, has a Base Centered Orthorhombic structure and Yellow color. Chlorine is a halogens element. Trivial name of Chlorine is halogens*. Know everything about Chlorine Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
Chlorine is a chemical element with symbol Cl and atomic number 17. It also has a relative atomic mass of 35.5. Chlorine is in the halogen group (17) and is the second lightest halogen following fluorine.
Read key information and facts about element Chlorine
Name | Chlorine |
Atomic Number | 17 |
Atomic Symbol | Cl |
Atomic Weight | 35.453 |
Phase | Gas |
Color | Yellow |
Classification | halogens |
Group in Periodic Table | 17 |
Group Name | fluorine family |
Period in Periodic Table | 3 |
Block in Periodic Table | p-block |
Electronic Configuration | [Ne] 3s2 3p5 |
Melting Point | -101.5 °C |
Boiling Point | -34.04 °C |
Electronic Shell Structure | [2, 8, 7] |
CAS Number | CAS7782-50-5 |
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 17 to find Chlorine 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 Chlorine on periodic table look for cross section of group 17 and period 3 in the modern periodic table.
The element Chlorine was discovered by Carl Wilhelm Scheele in year 1774 in Sweden . Chlorine derived its name from the Greek word chloros, meaning 'greenish yellow'
The table below shows the abundance of Chlorine in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
Ppb by weight (1ppb =10^-7 %) | |
---|---|
Abundance in Universe | 1e-06 |
Abundance in Sun | 8e-06 |
Abundance in Meteorites | 0.00037 |
Abundance in Earth's Crust | 0.00017 |
Abundance in Oceans | 0.02 |
Abundance in Humans | 0.0012 |
The solid state structure of Chlorine is Base Centered Orthorhombic.
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.
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 |
---|---|---|
622.35 | 445.61 | 817.85 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 | Cmca |
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Space Group Number | 64 | |
Crystal Structure | Base Centered Orthorhombic |
Chlorine atoms have 17 electrons and the electronic shell structure is [2, 8, 7] with Atomic Term Symbol (Quantum Numbers) 2P3/2.
Atomic Number | 17 |
Number of Electrons (with no charge) | 17 |
Number of Protons | 17 |
Mass Number | 35 |
Number of Neutrons | 18 |
Shell structure (Electrons per energy level) | [2, 8, 7] |
Electron Configuration | [Ne] 3s2 3p5 |
Valence Electrons | 3s2 3p5 |
Oxidation State |
-1
1;2;3;4;5;6;7 |
Atomic Term Symbol (Quantum Numbers) | 2P3/2 |
Shell Structure of Chlorine - Electrons per energy level
n | s | p | d | f | |
---|---|---|---|---|---|
1 | K | 2 | |||
2 | L | 2 | 6 | ||
3 | M | 2 | 5 |
The ground state electronic configuration of Neutral Chlorine atom is [Ne] 3s2 3p5. The portion of Chlorine configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ne]. 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 3s2 3p5, electrons in the outermost shell that determine the chemical properties of the element.
Complete ground state electronic configuration for the Chlorine atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p5
Chlorine atomic radius is 79 pm, while it's covalent radius is 99 pm.
Atomic Radius |
79 pm (0.79 Å) |
Atomic Volume | 11.030802738 cm3 |
Covalent Radius | 99 pm (0.99 Å) |
Van der Waals Radius | 175 pm |
Neutron Cross Section | 35.3 σa/barns |
The electron affinity of Chlorine is 349 kJ/mol
Valence | 5 |
Electronegativity | 3.16 |
ElectronAffinity | 349 kJ/mol |
Refer to table below for Ionization energies of Chlorine
Ionization energy number | Enthalpy - kJ/mol |
---|---|
1 | 1251.2 |
2 | 2298 |
3 | 3822 |
4 | 5158.6 |
5 | 6542 |
6 | 9362 |
7 | 11018 |
8 | 33604 |
9 | 3.86×104 |
10 | 43961 |
Refer to below table for Chlorine Physical Properties
Density | 3.214 g/l |
Molar Volume | 11.030802738 cm3 |
Young Modulus | N/A |
Shear Modulus | N/A |
Bulk Modulus | 1.1 GPa |
Poisson Ratio | N/A |
Mohs Hardness | N/A |
Vickers Hardness | N/A |
Brinell Hardness | N/A |
Chlorine is Insulator of electricity. Refer to table below for the Electrical properties of Chlorine
Electrical Conductivity | 0.01 S/m |
Resistivity | 100 m Ω |
Superconducting Point | N/A |
Thermal Conductivity | 0.0089 W/(m K) |
Thermal Expansion | N/A |
Magnetic Type | Diamagnetic |
Curie Point | N/A |
Mass Magnetic Susceptibility | -7.2×10-9 |
Molar Magnetic Susceptibility | -5.11×10-10 |
Volume Magnetic Susceptibility | -2.31×10-8 |
Refractive Index | 1.000773 |
Speed of Sound | 206 m/s |
Refer to table below for Thermal properties of Chlorine
Melting Point | 171.6 K (-101.5 °C) |
Boiling Point | 239.11 K (-34.04 °C) |
Critical Temperature | 416.9 K |
Superconducting Point | N/A |
Heat of Fusion | 3.2 kJ/mol |
Heat of Vaporization | 10.2 kJ/mol |
Heat of Combustion | N/A |
Isotopes of rhodium. Naturally occurring Chlorine has 2 stable isotope - 35Cl, 37Cl.
Isotope | Isotope Mass | % Abundance | T half | Decay Mode |
---|---|---|---|---|
28Cl | ||||
29Cl | ||||
30Cl | ||||
31Cl | ||||
32Cl | ||||
33Cl | ||||
34Cl | ||||
35Cl | 75.78% | Stable | N/A | |
36Cl | ||||
37Cl | 24.22% | Stable | N/A | |
38Cl | ||||
39Cl | ||||
40Cl | ||||
41Cl | ||||
42Cl | ||||
43Cl | ||||
44Cl | ||||
45Cl | ||||
46Cl | ||||
47Cl | ||||
48Cl | ||||
49Cl | ||||
50Cl | ||||
51Cl |
CAS Number | CAS7782-50-5 |
RTECS Number | RTECSFO2100000 |
DOT Hazard Class | N/A |
DOT Numbers | N/A |
EU Number | N/A |
NFPA Fire Rating | N/A |
NFPA Hazards | N/A |
NFPA Health Rating | N/A |
NFPA Reactivity Rating | N/A |
Autoignition Point | N/A |
Flashpoint | N/A |
List of unique identifiers to search the element in various chemical registry databases
Database | Identifier number |
---|---|
CAS Number - Chemical Abstracts Service (CAS) | CAS7782-50-5 |
CID Number | CID24526 |
Gmelin Number | N/A |
NSC Number | N/A |
RTECS Number | RTECSFO2100000 |
Metalloid |
Nonmetals |
Other Nonmetals | |
Halogens | Noble Gas |
Metals |
|
Alkali Metals | Alkaline Earth Metals |
Transition Metals | Post-Transition Metals |
Lanthanide | Actinide |