SBr4 Molecular Geometry - Science Education and Tutorials

Q: What is the molecular notation for SBr4 molecule?

SBr4 molecular notation is AX4N1

Sulfur tetrabromide(SBr4) has the composition of one sulfur and four bromine atoms. What is the molecular geometry of sulfur tetrabromide?. Drawing and predicting the SBr4 molecular geometry is very easy by following the given method. Here in this post, we described step by step to construct SBr4 molecular geometry. Sulfur and bromine come from the 16th and 17th family groups in the periodic table. Sulfur and bromine have six and seven valence electrons respectively.

Key Points To Consider When drawing The SBr4 Molecular Geometry

A three-step approach for drawing the SBr4 molecular can be used. The first step is to sketch the molecular geometry of the SBr4 molecule, to calculate the lone pairs of the electron in the central sulfur atom; the second step is to calculate the SBr4 hybridization, and the third step is to give perfect notation for the SBr4 molecular geometry.

The SBr4 molecular geometry is a diagram that illustrates the number of valence electrons and bond electron pairs in the SBr4 molecule in a specific geometric manner. The geometry of the SBr4 molecule can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory) and molecular hybridization theory, which states that molecules will choose the SBr4 geometrical shape in which the electrons have from one another in the specific molecular structure.

Finally, you must add their bond polarities characteristics to compute the strength of the S-Br bond (dipole moment properties of the SBr4 molecular geometry). The sulfur-bromine bonds in the sulfur tetrabromide molecule(SBr4), for example, are polarised toward the more electronegative value bromine atom, and because all (S-Br) bonds have the same size and polarity, their sum is non zero due to the SBr4 molecule’s bond dipole moment, and the SBr4 molecule is classified as a nonpolar molecule (due to less electronegativity difference).

The molecule of sulfur tetrabromide (with bipyramidal trigonal shape SBr4 molecular geometry) is tilted at slightly less than 102 and 173 degrees. It has a difference in electronegativity values between bromine and sulfur atoms, with bromine’s pull the electron cloud being greater than sulfur’s. As a result, it has a permanent dipole moment in its molecular structure. The SBr4 molecule has a dipole moment due to an unequal charge distribution of negative and positive charges.

Overview: SBr4 electron and molecular geometry

According to the VSEPR theory, SBr4 possesses a bipyramidal trigonal molecular geometry and SBr4-like electron geometry. Because the center atom, sulfur, has four S-Br bonds with the bromine atoms surrounding it. The Br-S-Br bond generates slightly less 102 and 173 degrees in the bipyramidal trigonal molecular geometry. The SBr4 molecule has a bipyramidal trigonal geometry shape because it contains four bromine atoms.

There are four S-Br bonds at the SBr4 molecular geometry. After linking the four bromine atoms in the bipyramidal trigonal form, it maintains the trigonal bipyramidal-like structure. In the SBr4 molecular geometry, the S-Br bonds have stayed in the four terminals of the trigonal bipyramidal molecule.

The center sulfur atom of SBr4 has one lone pair of electrons, resulting in bipyramidal electron geometry. However, the molecular geometry of SBr4 looks like a trigonal bipyramidal and one lone pair out of the plane. It’s the SBr4 molecule’s asymmetrical geometry. As a result, the SBr4 molecule is nonpolar.

How to find SBr4 molecular geometry and hybridization

Calculating lone pairs of electron on sulfur in the SBr4 molecular geometry:

1.Determine the number of lone pairs on the core be an atom of the SBr4 Lewis structure.
Because the lone pairs on sulfur are mostly responsible for the SBr4 molecule geometry distortion, we need to calculate out how many there are on the central sulfur atom of the Lewis structure.

Use the formula below to find the lone pair on the sulfur atom of the SBr4 molecule.
L.P(S) = V.E(S) – N.A(S-Br)/2

Lone pair on the central sulfur atom = L.P(S)
The core central sulfur atom’s valence electron = V.E(S)
Number of S-Br bonds = N.A (S-Br)
calculation for sulfur atom lone pair in SBr4 molecule

For instance of SBr4, the central atom, sulfur, has six electrons in its outermost valence shell and four S-Br bond connections.

As a result of this, L.P(S) = (6 –4)/2=1

In the SBr4 electron geometry structure, the lone pair on the central sulfur atom is one. It means there is one lone pair in the core sulfur atom. These lone pair on the central sulfur atom is responsible for the SBr4 molecular geometry distortion.

If you imagine, there is no lone pair on the sulfur atom of SBr4 molecule. Then , no electronic repulsion of S-Br bond pair and lone pair in the SBr4. That gives stable trigonal bipyramidal geometry.

But in reality, SBr4 molecule undergoes distortion in its geometry due to the lone pair of electron on the sulfur atom. This leads bipyramidal trigonal geometry for SBr4 molecule.

Calculate the number of molecular hybridizations of SBr4 molecule

What is SBr4 hybrizidation? This is a very fundamental question in the field of molecular chemistry. All the molecules made by atoms. In chemistry, atoms are the fundamental particles. There are four different types of orbitals in chemistry. They are named as s, p, d, and f orbitals.

The entire periodic table arrangement are based on these orbital theory. Atoms in the periodic table are classified as follows:

s- block elements
p- block elements
d-block elements
f-block elements
Atoms are classified in the periodic table

SBr4 molecule is made of one sulfur and four bromine atoms. The sulfur atom has s, p, and d orbital. bromine comes as the first element in the periodic table. The bromine atom has s and p orbitals.

When these atoms combine to form the SBr4 molecule, its orbitals mixed and form unique molecular orbitals due to hybridization.

How do you find the SBr4 molecule’s hybridization? We must now determine the molecular hybridization number of SBr4.

The formula of SBr4 molecular hybridization is as follows:
No. Hyb of SBr4 = N.A(S-Br bonds) + L.P(S)
No. Hy of SBr4= the number of hybridizations of SBr4
Number of S-Br bonds = N.A (S-Br bonds)
Lone pair on the central sulfur atom = L.P(S)
Calculation for hybridization number for SBr4 molecule

In the SBr4 molecule, sulfur is a core atom with four bromine atoms connected to it and one lone pair. The number of SBr4 hybridizations (No. Hyb of SBr4) can then be estimated using the formula below.

No. Hyb of SBr4= 4+1 =5

The SBr4 molecule hybridization is five. The sp3d hybridization is formed when one S orbital, three p orbitals, and one d orbital join together to form a molecular orbital.

Molecular Geometry Notation for SBr4 Molecule :

Determine the form of SBr4 molecular geometry using VSEPR theory. The AXN technique is commonly used when the VSEPR theory is used to calculate the shape of the SBr4 molecule.

The AXN notation of SBr4 molecule is as follows:
The center sulfur atom in the SBr4 molecule is denoted by the letter A.
The bound pairs (S-Br) of electrons to the core sulfur atom are represented by X.
The lone pairs of electrons on the center sulfur atom are denoted by the letter N.
Notation for SBr4 molecular geometry

We know that sulfur is the core atom, with four electron pairs bound (four S-Br) and one lone pair. The general molecular geometry formula for SBr4 is AX4N1.

According to the VSEPR theory, if the SBr4 molecule has an AX4N1 generic formula, the molecular geometry and electron geometry will both be bipyramidal trigonal forms.

Name of Molecule	sulfur tetrabromide
Chemical molecular formula	SBr4
Molecular geometry of SBr4	Bipyramidal trigonal
Electron geometry of SBr4	Bipyramidal trigonal
Hybridization of SBr4	sp3d
Bond angle (Br-S-Br)	slightly less than 102 º and 173º degree
Total Valence electron for SBr4	34
The formal charge of SBr4 on sulfur	0

Summary:

In this post, we discussed the method to construct SBr4 molecular geometry, the method to find the lone pairs of electrons in the central sulfur atom, SBr4 hybridization, and SBr4 molecular notation. Need to remember that, if you follow the above-said method, you can construct the SBr4 molecular structure very easily.