What are Halogens?

The halogens room the aspects that form group 17 of the periodic table. They are reactive nonmetals and include fluorine, chlorine, bromine, and also iodine.

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Halogens are highly reactive non-metals. These elements greatly resemble in residential property with each other. Team 17 facets are jointly called together halogens (In Greek: halo means salt and also genes median producing, so jointly salt producing) and it is composed of fluorine, chlorine, bromine, iodine, and also astatine.

The similarity come this level is not discovered in other groups of the periodic table. They have a regular gradation in the physical and also chemical properties. Astatine is the just radioactive aspect in the group. They have seven electron in their outermost covering (ns2np5) and are quick of one electron from the construction of the nearest noble gas. The chemistry properties and also reactivity the an aspect are figured out by the oxidation state showed by them.


Oxidation State

All the aspects of the halogen household exhibit -1 oxidation state. However, aspects such together chlorine, bromine, and iodine likewise show +1, +3, +5 and +7 state.The oxides and also oxoacids of chlorine and bromine have actually +4 and +6 states. There room no valence shells d orbitals in fluorine atom and also therefore it cannot broaden its octet.Fluorine being the most electronegative facet exhibits only -1 oxidation state.

Chemical Properties

1. Halogens are very reactive, they react with metals and non-metals in order to kind halides. Their reactivity decreases together we move down the group. Halogens have strong oxidizing properties. F2 is the strongest oxidizing halogen. It easily oxidizes various other halide ions current in solution or in the hard phase. In general, a halogen oxidizes halide ion which is of greater atomic number. For example:

F2 + 2X– → 2F– + X2 (X = Cl, Br or I)

From the typical electrode potential, the to decrease oxidizing ability of halogen deserve to be easily observed.

2. The family member oxidizing nature that halogens have the right to be depicted by your reactions v water. Fluorine oxidizes water come oxygen. Vice versa, chlorine and bromine react with water in stimulate to type respective hydrohalic and also hypohalous acids. Iodine reacts v water in a non-spontaneous way. I– have the right to be oxidized by water in the acidic medium. Because that example:

4 I– (aq) + 4H+ (aq) + O2 (g) → 2I2(s) + 2H2O (l)

General characteristics of Halogen Family:

1. Electronic construction of Halogen Family


Members of the halogen family have seven valence electrons, the is, they have seven electron in your outermost orbit. Thus, they space one electron brief of the nearest noble gas configuration. The basic configuration the the halogen household is offered as ns2np5.

2. Atomic and Ionic Radii the Halogen Family

The members of group 17 have actually the smallest atomic radii in their respective periods. This is attributed to the fact that they have a maximum effective nuclear charge. Atomic and also ionic radii boost from optimal to bottom in a team thus, it increases from fluorine to iodine because of the increasing number of quantum shells.


3. Ionisation Enthalpy the Halogen Family

Members of team 17 have actually very small or no tendency to lose an electron. Thus, they have a an extremely high value of ionisation enthalpy. Ionisation enthalpy reduce from peak to bottom in the group as result of the increase in atom size.

4. Electron gain Enthalpy of Halogen Family


The atoms of group 17 aspects are just one electron quick of attaining secure noble gas configurations. Thus, these aspects have a maximum an unfavorable electron gain enthalpy in the corresponding periods. Electron acquire enthalpy the these elements becomes less an adverse as we relocate down the group as result of the increase in atomic size. However, chlorine has a an ext negative worth of electron obtain enthalpy v respect come fluorine.

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5. Electronegativity the Halogen Family


The facets of group 17 have a an extremely high worth of electronegativity. The electronegativity decreases down the group due to the diminish in reliable nuclear charge. Thus, fluorine is the most electronegative element.