How to draw Br2 Lewis Structure - Science Education and Tutorials

Q: What is the Br2 Lewis structure?

Br2 Lewis structure is dot representation

Q: What is the formal charge on the Br2 Lewis structure?

Zero charges on the Br2 molecular structure

The liquid bromine chemical formula is Br2. Drawing Br2 Lewis Structure is very easy to by using the following method. Here in this post, we described step by step method to construct Br2 Lewis Structure. The diatomic bromine molecule elements come as members of the halogen family group from the periodic table. The valence electrons in the bromine atom are seven. Liquid bromine is used to make chemical corrosive reagents for organic chemical reactions as a brominating agent in organic chemistry.

Table of Contents

Key Points To Consider When Drawing The Br2 Electron Dot Structure

A three-step approach for drawing the Br2 Lewis structure can be used. The first step is to sketch the Lewis structure of the Br2 molecule, to add valence electrons around the two bromine atoms, and the final step is to combine the two bromine diatomic atoms to get the Br2 Lewis Structure.

The Br2 Lewis structure is a diagram that illustrates the number of valence electrons and bond electron pairs in the Br2 molecule. The geometry of the Br2 molecule can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory), which states that molecules will choose the Br2 geometrical shape in which the electrons have from one another.

Finally, you must add their bond polarities to compute the strength of the one Br-Br single bonds (dipole moment properties of the Br2 molecule). The bromine-bromine bonds in bromine molecule(Br2), for example, are polarised equally the more electronegative bromine in Br2 molecule, and because both bonds have the same size and are located around one bromine terminal of the two tetrahedral or linear structure with three lone pairs (in total six electrons) on the bromine atoms, their sum of dipole moment is zero due to the Br2 molecule’s bond dipole moment and two bromine atoms canceled the polarity. Because Br-Br bonds polarity is canceled in the Br2 molecule due to the presence of two equal sharing in the linear geometry. The bromine(Br2) molecule is classified as a nonpolar molecule.

The molecule of diatomic bromine(with tetrahedral or linear-shaped molecular geometry) is tilted, the bond angles between bromine and bromine are 180 degrees. It has a no difference in electronegativity values between bromine and other bromine atoms, with both bromine’s pull being equal in the Br2 molecule. But they canceled each other due to the symmetrical linear structure with three lone pairs in the molecular geometry of the Br2 molecule.

As a result, it has the zero dipole moment. The Br2 molecule has a zero dipole moment due to an equal charge distribution of negative charges on both bromine terminals. But both bromine atoms fall on the halogen family groups in the periodic table. The bromine atom is a more electronegative value than iodine atom in the halogen family group. The Br2 molecule has the net dipole moment of 0D value in the ground state energy level.

Br2 molecule has one Br-Br single bond. Its dipole moment in the ground state is totally different as compared with the excited state. If it absorbs light may be from visible or UV light. It undergoes pi to pi star and n to pi star transition from ground state energy level to excited state energy level. In the excited state energy level, the Br2 molecule shows a definite dipole moment. But it is very dynamic in nature.

Molecules can be classified as polar or nonpolar. The molecule polar behaves in a different manner as compared to nonpolar.

Overview: Br2 Lewis Structure

The terminal atom is bromine, which is bordered on two terminals with bromine atoms( in tetrahedral or linear geometry), and three lone pairs on the two bromine atoms in the tetrahedral or linear molecular geometry. Bromine has seven outermost valence electrons, indicating that it possesses seven electrons in its outermost shell. To complete the octet of the two bromine atoms requires one valence electron on each of their outermost shell.

One bromine atom establishes covalent connections with the other terminal bromine atom as a result, leaving each bromine atom with three lone pairs. There are three lone pairs of electrons on the bromine terminal atom that resists the bond pairs of the Br-Br bond. According to VSEPR theory, the Br-Br bond pairs polarity lead the Br2 molecule to take on the linear or tetrahedral geometry structure.

The Br2 molecule’s one Br-Br bond is arranged in symmetrical polarity order around the linear or tetrahedral molecular geometry, giving rise to the Br2 molecular shape. The bond order of the Br2 molecule is one. The Br2 molecule has a tetrahedral or linear molecular geometry because there is an electrical repulsion between the lone pairs of electrons in bromine and one single bond pair(Br-Br) of the Br2 molecule.

Lewis structure of Br2 has dot electron representative structure. Valence electrons of atoms undergo orbitals mixing in the chemical reactions, giving new types of molecular species of Br2. The molecule is nothing but a bundle of valence electrons from the atoms. But it is converted to bond pairs and lone pairs in the molecular structure.

Electronegative value Difference Calculation of Br2 Molecule:

Bromine and bromine Electronegative difference in Br2 molecule:

The bromine atom has an electronegativity of 2.96 in the Br2 molecule. The difference in electronegativity of bromine and bromine can be estimated using the method below.

The electronegative value difference between bromine and bromine in Br2 molecule
Electronegativity value of bromine= 2.96
Electronegativity value of bromine= 2.96
Difference of electronegativity value between bromine and bromine in Br2 molecule = 2.96 – 2.96 = 0.00
Electronegativity difference between Br-Br bond calculation of Br2 molecule

The electronegative difference between bromine and bromine is less than 0.5. This indicated the bond polarity moves near to nonpolar nature. Br-Br bond polarity in the Br2 molecule is nonpolar.

Because of this difference in electronegativity of bromine and bromine atoms, the Br2 molecule’s Br-Br bond becomes nonpolar. The total net dipole moment of the Br2 molecule is zero due to the cancellation of the bond dipole moment in the linear or tetrahedral geometry due to the presence of three lone pairs of electrons. The electronegativity of an atom is the strength with which it may attract bound electron pairs to its side. The polarity of HBr is discussed in our previous post.

As a result, the Br-Br bond’s dipole moment is higher due to the polarization of the bonds and three lone pairs of electrons on bromine, and all Br-Br bonds’ dipoles are arranged in the symmetrical Br2 molecular geometry. The Br2 molecule has a zero net dipole moment.

The electron dot structure of the Br2 molecule is also known as the Br2 Lewis structure. It determines the number of outermost valence electrons as well as the electrons engaged in the Br2 molecule’s bond formation. The outermost valence electrons of the Br2 molecule must be understood while constructing the Lewis structure of the molecule.

The bromine atom is the terminal element in Br2 molecular geometry, with seven electrons in its outermost valence electron shell.

The Br2 has a total of 14 valence electrons as a result of the foregoing above-said reasoning. With the terminal bromine atom, the other terminal with one bromine atom forms covalent bond, leaving the bromine atom with three lone pairs(12 electron total) in the middle of linear or tetrahedral geometry.

Because three lone pairs on the terminal bromine atoms create interaction with Br-Br bond pairs(but it is negligible in the ground state of the Br2 molecule). The bond angle of the Br-Br bond in the linear or tetrahedral molecular geometry is approximately 180 degrees. This angle is greater than the CH4 molecule bond angle. The Br-Br bond length is longer than the Cl-Cl bond length.

To sketch the Br2 Lewis structure by following these instructions:

Step-1: Br2 Lewis dot Structure by counting valence electrons on the bromine atom

To calculate the valence electron of each atom in Br2, look for its periodic group from the periodic table. The halogen group families, which is the 17th in the periodic table, are made up of two bromine atoms. In their outermost shells, bromine and bromine have seven and seven valence electrons respectively.

Calculate the total number of valence electrons in the Br2 molecule’s outermost valence shell. The first step is to determine how many electrons are in the Br2 Lewis structure’s outermost valence shell. An electron in an atom’s outermost shell is known as a valence electron. It is represented by dots in the Br2 Lewis diagram. The Br2 molecule’s core bromine atom can be represented as follows:

Total outermost valence shell electron of bromine atom in Br2= 7
Total outermost valence shell electron of bromine atom in Br2= 7
The Br2 molecule has one terminal bromine and other terminal bromine atoms. Then the total outermost valence shell electrons can be calculated as follows
∴ Total outermost valence shell electrons available for Br2 Lewis structure( dot structure) = 7+7= 14 valence electrons in Br2.
calculation of total valence electron of Br2 molecule

Choose the atom with the least electronegative value atom and insert it in both terminals of the molecular geometry of Br2. We’ll choose the least electronegative value atom in the Br2 molecule to place in the terminal of the Br2 Lewis structure diagram in this phase.

The first step is to put seven valence electrons around the bromine atom as given in the figure.

Step-2: Lewis dot Structure for Br2 generated from step-1

Connect the two terminal atoms of the Br2 molecule with one single Br-Br bond. In this stage, use one bromine atom on the outside of the Br2 molecule to the other terminal bromine atom in the molecular geometry.

Count how many electrons from the outermost valence shell have been used in the Br2 structure so far. Br-Br single bond carries two electrons because the bromine atom is connected to another bromine atom by Br-Br single bonds. Bond pairings of Br-Br are what they’re called.

So, out of the total of 14 valence electrons available for the Br2 Lewis structure, we used four electrons for the Br2 molecule’s one Br-Br single bond. The Br2 molecule has three lone pairs of electrons in the two-terminal bromine atoms.

Place the valence electrons in the Br-Br bond pair starting with the one terminal bromine, another bromine atom in the Br2 molecule. In the Br2 Lewis structure diagram, we always begin by introducing valence electrons from the terminal bromine atom(in step1). As a result, wrap around the terminal bromine atom’s bond pair valence electrons first (see figure for step1).

The bromine atom in the molecule gets only 14 electrons around its molecular structure. This central bromine atom is octet stable. But it has three lone pairs. Bromine liquid(Br2) is a brownish liquid gas. Bromine is very corrosive in nature. It is one of the very reactive chemical reagents.

Bromine requires 8 electrons in its outermost valence shell to complete the molecular octet stability, two electrons bond pairs in one Br-Br single bond, and three lone pairs in the terminal bromine atom. Bromine already shares 8 electrons to the one Br-Br single bonds.

We’ve positioned 8 electrons around the one-terminal bromine atoms(step-1), which is represented by a dot, in the Br2 molecular structure above. The bromine atom completes its molecular octet stability in the Br2 molecule because it possesses 2 electrons in its (one Br-Br single bonds) bond pairs with one bromine in the outermost valence shell.

Count how many outermost valence shell electrons have been used so far using the Br2 Lewis structure. One electron bond pairs are shown as dots in the Br2 chemical structure, whereas one single bond contains two electrons. The outermost valence shell electrons of the Br2 molecule(bond pairs) are 2 as a result of the calculation. The total valence electron in a bromine atom is 8.

So far, we’ve used 8 of the Br2 Lewis structure’s total 14 outermost valence shell electrons. Three lone pairs of electrons on each bromine atoms in the linear or tetrahedral geometry of the Br2 molecule.

Complete the terminal Br2 atom stability and, if necessary, apply a covalent bond. The terminal bromine atom undergoes octet stability(due to one single bond pair of electrons).

The core atom in the Br2 Lewis structure is bromine, which is bonded to the one terminal bromine atom by single bonds (one Br-Br). With the help of one single bond, it already shares 8 electrons. As a result, the bromine follows the octet rule and has 8 electrons surrounding it on the one terminal of the Br2 molecule’s linear or tetrahedral geometry.

How to calculate the formal charge on bromine and other bromine atoms in Br2 Lewis Structure?

Calculating formal charge on the bromine of Br2 molecule:

The formal charge on the Br2 molecule’s bromine central atom often corresponds to the actual charge on that bromine terminal atom. In the following computation, the formal charge will be calculated on the terminal bromine atom of the Br2 Lewis dot structure.

To calculate the formal charge on the terminal bromine atom of the Br2 molecule by using the following formula:
The formal charge on the bromine atom of Br2 molecule= (V. E(Br)– L.E(Br) – 1/2(B.E))
V.E (Br) = Valence electron in a bromine atom of Br2 molecule
L.E(Br) = Lone pairs of an electron in the bromine atom of the Br2 molecule.
B.E = Bond pair electron in Br atom of Br2 molecule
calculation of formal charge on bromine atom in Br2 molecule

The bromine terminal atom (one single bond connected to one bromine atom) of the Br2 molecule has seven valence electrons, three lone pairs of electrons(six electrons), and 2 bonding pairing valence electrons. Put these values for the bromine atom in the formula above.

Formal charge on bromine atom of Br2 molecule = (7- 6-(2/2)) =0

In the Lewis structure of Br2, the formal charge on the terminal bromine atom is zero.

Summary:

In this post, we discussed the method to construct the Br2 Lewis structure. First, the valence electrons are placed around the two bromine atoms. Finally, when we combined the first and second steps. It gives Br2 Lewis structure. Need to remember that, if you follow the above-said method, you can construct molecular dot structure very easily.