Element 53 of Periodic table is Iodine with atomic number 53, atomic weight 126.90447. Iodine, symbol I, has a Base Centered Orthorhombic structure and SlateGray color. Iodine is a halogens element. Trivial name of Iodine is halogens*. Know everything about Iodine Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
Iodine is a chemical element with symbol I and atomic number 53. The name is from Greek ἰοειδής ioeidēs, meaning violet or purple, due to the color of iodine vapor. Iodine and its compounds are primarily used in nutrition, and industrially in the production of acetic acid and certain polymers.
Read key information and facts about element Iodine
Name | Iodine |
Atomic Number | 53 |
Atomic Symbol | I |
Atomic Weight | 126.90447 |
Phase | Solid |
Color | SlateGray |
Classification | halogens |
Group in Periodic Table | 17 |
Group Name | fluorine family |
Period in Periodic Table | 5 |
Block in Periodic Table | p-block |
Electronic Configuration | [Kr] 4d10 5s2 5p5 |
Melting Point | 113.7 °C |
Boiling Point | 184.3 °C |
Electronic Shell Structure | [2, 8, 18, 18, 7] |
CAS Number | CAS7553-56-2 |
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 53 to find Iodine 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 Iodine on periodic table look for cross section of group 17 and period 5 in the modern periodic table.
The element Iodine was discovered by Bernard Courtois in year 1811 in France . Iodine derived its name from French iode (after the Greek ioeides, 'violet')
The table below shows the abundance of Iodine in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
Ppb by weight (1ppb =10^-7 %) | |
---|---|
Abundance in Universe | 1×10-7% |
Abundance in Sun | N/A |
Abundance in Meteorites | 2.5e-07 |
Abundance in Earth's Crust | 4.9e-07 |
Abundance in Oceans | 6×10-6% |
Abundance in Humans | 2e-07 |
The solid state structure of Iodine 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 |
---|---|---|
718.02 | 471.02 | 981.03 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 |
Iodine atoms have 53 electrons and the electronic shell structure is [2, 8, 18, 18, 7] with Atomic Term Symbol (Quantum Numbers) 2P3/2.
Atomic Number | 53 |
Number of Electrons (with no charge) | 53 |
Number of Protons | 53 |
Mass Number | 127 |
Number of Neutrons | 74 |
Shell structure (Electrons per energy level) | [2, 8, 18, 18, 7] |
Electron Configuration | [Kr] 4d10 5s2 5p5 |
Valence Electrons | 5s2 5p5 |
Oxidation State |
-1
1;3;4;5;6;7 |
Atomic Term Symbol (Quantum Numbers) | 2P3/2 |
Shell Structure of Iodine - Electrons per energy level
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 | 5 |
The ground state electronic configuration of Neutral Iodine atom is [Kr] 4d10 5s2 5p5. The portion of Iodine configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Kr]. 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 4d10 5s2 5p5, electrons in the outermost shell that determine the chemical properties of the element.
Complete ground state electronic configuration for the Iodine atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p5
Iodine atomic radius is 115 pm, while it's covalent radius is 133 pm.
Atomic Radius |
115 pm (1.15 Å) |
Atomic Volume | 25.6891639676 cm3 |
Covalent Radius | 133 pm (1.33 Å) |
Van der Waals Radius | 198 pm |
Neutron Cross Section | 6.2 σa/barns |
The electron affinity of Iodine is 295.2 kJ/mol
Valence | 7 |
Electronegativity | 2.66 |
ElectronAffinity | 295.2 kJ/mol |
Refer to table below for Ionization energies of Iodine
Ionization energy number | Enthalpy - kJ/mol |
---|---|
1 | 1008.4 |
2 | 1845.9 |
3 | 3180 |
Refer to below table for Iodine Physical Properties
Density | 4.94 g/cm3 |
Molar Volume | 25.6891639676 cm3 |
Young Modulus | N/A |
Shear Modulus | N/A |
Bulk Modulus | 7.7 GPa |
Poisson Ratio | N/A |
Mohs Hardness | N/A |
Vickers Hardness | N/A |
Brinell Hardness | N/A |
Iodine is Insulator of electricity. Refer to table below for the Electrical properties of Iodine
Electrical Conductivity | 1×10-7 S/m |
Resistivity | 1×107 m Ω |
Superconducting Point | N/A |
Thermal Conductivity | 0.449 W/(m K) |
Thermal Expansion | N/A |
Magnetic Type | Diamagnetic |
Curie Point | N/A |
Mass Magnetic Susceptibility | -4.5×10-9 |
Molar Magnetic Susceptibility | -1.14×10-9 |
Volume Magnetic Susceptibility | -2.22e-05 |
Refractive Index | N/A |
Speed of Sound | N/A |
Refer to table below for Thermal properties of Iodine
Melting Point | 386.85 K (113.7 °C) |
Boiling Point | 457.4 K (184.3 °C) |
Critical Temperature | 819 K |
Superconducting Point | N/A |
Heat of Fusion | 7.76 kJ/mol |
Heat of Vaporization | 20.9 kJ/mol |
Heat of Combustion | N/A |
Isotopes of rhodium. Naturally occurring Iodine has 1 stable isotope - 127I.
Isotope | Isotope Mass | % Abundance | T half | Decay Mode |
---|---|---|---|---|
108I | ||||
109I | ||||
110I | ||||
111I | ||||
112I | ||||
113I | ||||
114I | ||||
115I | ||||
116I | ||||
117I | ||||
118I | ||||
119I | ||||
120I | ||||
121I | ||||
122I | ||||
123I | ||||
124I | ||||
125I | ||||
126I | ||||
127I | 100% | Stable | N/A | |
128I | ||||
129I | ||||
130I | ||||
131I | ||||
132I | ||||
133I | ||||
134I | ||||
135I | ||||
136I | ||||
137I | ||||
138I | ||||
139I | ||||
140I | ||||
141I | ||||
142I | ||||
143I | ||||
144I |
CAS Number | CAS7553-56-2 |
RTECS Number | RTECSNN1575000 |
DOT Hazard Class | 8 |
DOT Numbers | 1759 |
EU Number | N/A |
NFPA Fire Rating | 0 |
NFPA Hazards | N/A |
NFPA Health Rating | 3 |
NFPA Reactivity Rating | 0 |
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) | CAS7553-56-2 |
CID Number | CID807 |
Gmelin Number | N/A |
NSC Number | N/A |
RTECS Number | RTECSNN1575000 |
Metalloid |
Nonmetals |
Other Nonmetals | |
Halogens | Noble Gas |
Metals |
|
Alkali Metals | Alkaline Earth Metals |
Transition Metals | Post-Transition Metals |
Lanthanide | Actinide |