Bromine, a chemicalelement with the symbol Br and atomic number 35, is a very reactive gas so thatdoes not occur in cost-free states but exists together halide salts or table salts. At standardtemperature and pressure, that is uncovered as a liquid choose mercury.

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You are below toknow valence electrons of bromine atom, aren’t you? Don’t worry together with brominevalence electrons us will define its valency also. But prior to that let’s havesome basic ideas around what these 2 terms are:

Difference BetweenValence Electrons and Valency

Valence electronsare the total variety of electrons existing in the outermost shell of an atom(i.e. In outermost orbital). The valence electrons for a neutral atom arealways definite, it cannot be varied (more or less) in any type of condition because that aparticular atom and also may or may not be same to the valency.


Valency is definedas the total number of electrons one atom have the right to lose, gain, or share in ~ the timeof bond formation to gain a stable digital configuration i.e. To finish anoctet. The valency of one atom deserve to be variable in different compounds orchemical reactions due to the different bonding circumstances. Most of the timevalency varies/changes early to change in oxidation and reduction states.

Bromine (Br)Valence Electrons

There are four simplesteps to find out the valence electrons because that bromine atom i beg your pardon are:

Step 1: uncover theAtomic Number


To discover out theatomic variety of bromine, we can use the routine table. V the assist of theperiodic table, we can easily see the the atomic number of bromine is 35. Asits atom number is 35, it has 35 protons, and for neutral bromine, the numberof protons is constantly equal to the variety of electrons i.e. Has 35 electrons inits nucleus.

Step 2: WriteElectron Configuration


Electronconfiguration is the arrangement of electron on the orbitals. The bromine atomhas a total of 35 electrons so, we need to put 35 electron in orbitals. Theelectrons will certainly be inserted in various orbitals follow to the power level:<1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f>. Now,

Bromine electronconfiguration Br (35) =1s22s22p63s23p63d104s24p5(completeconfiguration).

= 4s² 3d¹⁰ 4p⁵(condensed configuration).

Step 3: DetermineValence Shell

As us know, thevalence shell of one atom deserve to be found from the highest variety of principlequantum numbers are expressed in the ax of n, and in 4s² 3d¹⁰ 4p⁵, the highest possible value the n is 4 so that the valence shell of bromine is4s² 3d¹⁰ 4p⁵.

Step 4: FindValence Electrons

The full number ofelectrons existing in the valence covering of an atom are referred to as valence electrons,and there are a total of 7 electrons present in the valence covering of bromine(4s² 3d¹⁰ 4p⁵). Thus,bromine has seven valence electrons.

Valency that Bromine(Br)

There space manydifferent ways to uncover out the valency of one atom which reflects the capability ofan atom come bond with other atoms. Valence describes how quickly an atom or afree radical can combine with various other chemical species. The valency of an atom isdetermined based upon the variety of electrons lost, gained, or common withanother atom at the time of shortcut formation.

An atom is claimed tobe stable as soon as its outermost shells have actually eight electron (except H & He).If the total number of electrons in outermost shells is between one come four,the atom has positive valency and also if electrons are in between four come eight, thevalency is calculate by individually from eight and valency will be zero. Atomshaving four outermost electrons own both optimistic and an adverse valency, andatoms having actually eight outermost electrons, valency will certainly be zero (i.e. Noblegases).

Elements favor brominecan reach the stable state (nearest inert gas configuration: Ar) by acquiring oneelectron.So that the valency that bromine is 1.

Mathematically, theelectronic configuration of bromine is 2, 8, 18, 7. And as us know, ifelectrons in the outermost shell exceed from 4, it need to be subtracted from 8. So,

ElectronConfiguration the bromine (Br) = 2, 8, 18, 7

We have the right to see theoutermost shell of bromine has actually 7 electron so, need to subtract that from 8.

8 – 7 = 1

That’s why valencyof bromine is 1.

Note: In general, brominehas a secure oxidation state of -1 most of the time however it have the right to differ insome compounds with values 0 (Br2), +1 (NaBrO), +3 (NaBrO2), +4 (BrO3), +5 (NaBrO3),+7 (NaBrO4). Perform not confuse through -1 or something else (+1, +3, +4, etc.) with a optimistic or an unfavorable sign, that is simply an oxidation number that can vary from compound to compound. But its valency is constantly 1 in any kind of case.

In an additional sense, abromine atom can type a maximum of one covalent link in a chemical bonding (For example:HBr, CH3Br, CaBr2, etc.), and that what valency is, the maximum capacity to formbonds through atoms at the moment of chemical bonding.

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We can additionally findthe valency that bromine v the aid of the routine table. As bromine belongsto team 17 (17A or VIIA) in addition to fluorine (F), chlorine (Cl), iodine (I), andastatine (At). This group elements are likewise called halogens. All these elementshave valency one.