What are Halogens?

The halogens are the facets that type group 17 the the regular table. They room reactive nonmetals and also include fluorine, chlorine, bromine, and iodine.

You are watching: What is the oxidation number of elements in group 17

Halogens are very reactive non-metals. These facets greatly resemble in home with every other. Group 17 facets are jointly called as halogens (In Greek: halo method salt and genes typical producing, so jointly salt producing) and it consists of fluorine, chlorine, bromine, iodine, and also astatine.

The similarity come this level is not discovered in other teams of the regular table. They have actually a continual gradation in the physical and also chemical properties. Astatine is the just radioactive facet in the group. They have actually seven electrons in their outermost shell (ns2np5) and also are quick of one electron from the configuration of the nearest noble gas. The chemical properties and reactivity that an element are established by the oxidation state exhibited by them.


Oxidation State

All the aspects of the halogen family members exhibit -1 oxidation state. However, facets such as chlorine, bromine, and iodine additionally show +1, +3, +5 and also +7 state.The oxides and also oxoacids of chlorine and bromine have +4 and also +6 states. There room no valence shells d orbitals in fluorine atom and therefore it cannot broaden its octet.Fluorine gift the most electronegative aspect exhibits just -1 oxidation state.

Chemical Properties

1. Halogens are very reactive, they react through metals and also non-metals in stimulate to form halides. Your reactivity decreases together we move down the group. Halogens have strong oxidizing properties. F2 is the the strongest oxidizing halogen. It conveniently oxidizes various other halide ions present in systems or in the hard phase. In general, a halogen oxidizes halide ion i beg your pardon is of higher atomic number. For example:

F2 + 2X– → 2F– + X2 (X = Cl, Br or I)

From the traditional electrode potential, the decreasing oxidizing ability of halogen can be quickly observed.

2. The relative oxidizing nature the halogens have the right to be shown by your reactions through water. Fluorine oxidizes water to oxygen. Vice versa, chlorine and bromine react v water in bespeak to kind respective hydrohalic and hypohalous acids. Iodine reacts v water in a non-spontaneous way. I– can be oxidized by water in the acidic medium. For example:

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

General features of Halogen Family:

1. Electronic configuration of Halogen Family


Members of the halogen family members have 7 valence electrons, that is, they have seven electrons in their outermost orbit. Thus, they room one electron short of the nearest noble gas configuration. The general configuration that the halogen family members is offered as ns2np5.

2. Atomic and Ionic Radii of Halogen Family

The members of group 17 have the smallest atomic radii in their respective periods. This is attributed come the fact that they have actually a maximum effective nuclear charge. Atomic and ionic radii boost from height to bottom in a group thus, it boosts from fluorine come iodine as result of the increasing variety of quantum shells.


3. Ionisation Enthalpy that Halogen Family

Members of team 17 have very tiny or no tendency to shed an electron. Thus, they have actually a really high value of ionisation enthalpy. Ionisation enthalpy to reduce from optimal to bottom in the group because of the increase in atomic size.

4. Electron gain Enthalpy that Halogen Family


The atoms of group 17 aspects are just one electron quick of attaining secure noble gas configurations. Thus, these elements have a maximum an unfavorable electron get enthalpy in the corresponding periods. Electron obtain enthalpy of these elements becomes less an adverse as we move down the group as result of the increase in atom size. However, chlorine has a much more negative value of electron obtain enthalpy through respect come fluorine.

See more: How Long Is Chicken Salad Good For In The Fridge, How Long Does Homemade Chicken Salad Last

5. Electronegativity of Halogen Family


The facets of team 17 have a very high worth of electronegativity. The electronegativity decreases under the group due to the diminish in effective nuclear charge. Thus, fluorine is the most electronegative element.