How to draw ZnBr2 Lewis Structure? - Science Education and Tutorials

Drawing ZnBr2 Lewis Structure is very easy. Here in this post, we described step by step method to construct ZnBr2 Lewis Structure.

Table of Contents

Key Points To Consider When Drawing The ZnBr2 Lewis Structure

A three-step approach for drawing the ZnBr2 Lewis structure can be used. The first step is to sketch the Lewis structure of the ZnBr2 molecule, to add valence electron around the Zinc atom; the second step is to valence electron to the two bromine atoms, and the final step is to combine the step1 and step2 to get the ZnBr2 Lewis Structure.

The ZnBr2 Lewis structure is a diagram that illustrates the number of valence electrons and bond electron pairs in the ZnBr2 molecule. It is basically a dissociable ionic molecule. The geometry of the ZnBr2 molecule can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory), which states that molecules will choose a ZnBr2 geometrical shape in which the electrons have from one another.

Finally, you must add their bond polarities to compute the strength of the Zn-Br bond (dipole moment properties of the ZnBr2 molecule). The Zinc-bromine bonds in Zinc bromide(ZnBr2), for example, are polarised toward the more electronegative bromine, and because both bonds have the same size and opposite to each other, their sum is zero due to the ZnBr2 molecule’s bond dipole moment, and the ZnBr2 molecule is classified as a nonpolar molecule.

The molecule of Zinc bromide (with linear geometry) is tilted at 180 degrees and has a difference in electronegativity values between bromine and Zinc atoms, with Zinc’s pull being less than bromine’s terminal in the ZnBr2 molecule. As a result, it has no dipole moment. The ZnBr2 molecule has no dipole moment due to an equal charge distribution of negative and positive charges.

ZnBr2 Lewis Structure:

The central atom is Zinc, which is bordered on two terminals with bromine atoms. Zinc has two outermost valence electrons, indicating that it possesses two electrons in its outermost shell, whereas bromine only has seven valence electrons in its outermost shell. To complete the octet of the bromine atom, a bromine terminal atom requires one electron. If you’re interested in learning more about the bromine octet rule, please see in our previous post.

Two bromine atoms establish covalent connections with the Zinc atom as a result, leaving the Zinc atom without any lone pairs. There are no lone pairs on the Zinc central atom that resist the bond pairs of the two Zn-Br. According to VSEPR theory, no electronic repulsion leads the ZnBr2 molecule to take on a linear molecular shape like NO2+ and CS2.

The ZnBr2 molecule’s Zn-Br bonds are arranged in a symmetrical order around the linear geometry, giving rise to the linear ZnBr2 shape. The ZnBr2 molecule has a linear molecular geometry because there is no electrical repulsion between them.

Electronegative Difference Calculation ZnBr2 Molecule:

Zinc has an electronegativity of 1.65, while bromine has an electronegativity of 3.16 in the ZnBr2 molecule. The difference in electronegativity can be estimated using the method below.

The electronegative value difference between Zinc and bromine
Electronegativity value of Zinc = 1.65
Electronegativity value of bromine= 3.16
Difference of electronegativity value between Zinc and bromine= 3.16 – 1.65 =1.51
Electronegativity difference between Zn-Br bond calculation of ZnBr2 molecule

Due to the difference in electronegativity value of greater than 0.5, the Zn-Br bond of the ZnBr2 molecule becomes polar. Because of this difference in electronegativity, the ZnBr2 molecule’s Zn-Br bond becomes polar. The electronegativity of an atom is the strength with which it may attract bound electron pairs to its side. The polarity of ZnBr2 is discussed in our previous post.

As a result, the Zn-Br bond’s dipole moment is high due to the polarization of the bonds, and all Zn-Br bonds’ dipoles are faced opposite to each other in the linear geometry. The ZnBr2 molecule’s total dipole moment is predicted to be 0 D. It has a partial negative charge for bromine atoms and a partial positive charge for the central Zinc atom.

The electron dot structure of the ZnBr2 molecule is also known as the ZnBr2 Lewis structure. It determines the number of outermost valence electrons as well as the electrons engaged in the ZnBr2 molecule’s bond formation. The outermost valence electrons of the ZnBr2 molecule must be understood while considering the Lewis structure of the molecule.

The Zinc atom is the middle element in ZnBr2 molecular geometry, with two electrons in its outermost valence electron shell, whereas the bromine atom has seven electrons in its outermost valence electron shell.

The ZnBr2 molecule has a total of 16 valence electrons as a result of the foregoing reasoning. With the core central Zinc atom, the two-terminal bromine atoms form covalent bonds, leaving the Zinc atom with no lone pairs on it.

The linear geometry and structure of the ZnBr2 molecules are similar to that of the carbon disulfide (CS2) molecule because no lone pairs of central Zinc atoms create interaction with Zn-Br bond pairs. The bond angle of the Br-Zn-Br bond is approximately 180 degrees. The Zn-Br bond length is 2.2370 or 2.2301 pm(picometer).

To sketch the ZnBr2 Lewis structure by following these instructions:

Step-1: ZnBr2 Lewis Structure

To calculate the valence electron of each atom in ZnBr2, look for its periodic group from the periodic table. The transition metal group and halogen families, which are the 12th and 17th groups in the periodic table, are both made up of Zinc and bromine atoms. In their outermost shells, Zinc and bromine have two and seven valence electrons, respectively.

Because Zinc and bromine are members of the periodic table’s transition metal group and halogen family groups, their valence electrons are two and seven, respectively.

Calculate the total number of electrons in the ZnBr2 molecule’s outermost valence shell. The first step is to determine how many electrons are in the ZnBr2 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 ZnBr2 Lewis diagram. The ZnBr2 molecule’s core carbon atom can be represented as follows:

Total outermost valence shell electron of Zinc atom in ZnBr2= 2
Total outermost valence shell electron of bromine atom in ZnBr2= 7
The ZnBr2 molecule has one central Zinc atom and two bromine atoms. Then the total outermost valence shell electrons can be calculated as follows
∴ Total outermost valence shell electrons available for ZnBr2 Lewis structure( dot structure) = 2 +2*7= 16 valence electrons in ZnBr2
calculation of total valence electron of ZnBr2 molecule

Choose the atom with the least electronegative value atom and insert it in the center of the molecular geometry of ZnBr2. We’ll choose the least electronegative value atom in the ZnBr2 molecule to place in the center of the ZnBr2 Lewis structure diagram in this phase. The electronegativity value in periodic groups grows from left to right in the periodic table and drops from top to bottom.

Step-2: ZnBr2 Lewis Structure

As a result, Zinc is the first atom in the periodic table’s transition metal 12 th family group. Bromine is the third member of the halogen family. The electronegative value of a Zinc atom is lower than that of a bromine atom. Furthermore, Zinc has a two electrons limit since bromine is the most electronegative element in the ZnBr2 molecule.

In a ZnBr2 Lewis structure diagram, the Zinc atom can be the center atom. As a result, central Zinc in the ZnBr2 Lewis structure, with all two bromines arranged in the two-terminal of linear geometry.

Step-3: ZnBr2 Lewis Structure

Connect the exterior and core central atom of the ZnBr2 molecule with two single bonds (Zn-Br). In this stage, use two single bonds to connect all two bromine atoms on the outside of the ZnBr2 molecule to the central Zinc atom in the middle.

Count how many electrons from the outermost valence shell have been used in the ZnBr2 structure so far. Each Zn-Br bond carries two electrons because each Zinc atom is connected to two bromine atoms by two Zn-Br bonds. Bond pairings are what they’re called.

So, out of the total of 16 valence electrons available for the ZnBr2 Lewis structure, we used 4 for the ZnBr2 molecule’s two single (Zn-Br) bonds. The ZnBr2 molecule has no lone pair electrons in the center of Zinc. We don’t need to put the extra electron in the molecular geometry of ZnBr2.

Place the valence electrons in the Zn-Br bond pairs starting with the core Zinc and two bromine atoms in the ZnBr2 molecule. In the ZnBr2 Lewis structure diagram, we always begin by introducing valence electrons from the central Zinc atom. As a result, wrap around the central Zinc atom’s bond pair valence electrons first.

Zinc requires 4 electrons in its outermost valence shell to complete the molecular stability. Zinc already shares 4 electrons thanks to the two single bonds. Then place the valence electron in the bromine atom, it placed around seven electrons. Totally, 12 valence electrons were placed on the two bromine atoms of the ZnBr2 molecule.

We’ve positioned four electrons around the central Zinc atom, which is represented by a dot, in the ZnBr2 molecular structure above. The Zinc atom completes its molecular stability in the ZnBr2 molecule because it possesses 4 electrons in its outermost valence shell.

Count how many outermost valence shell electrons have been used so far using the ZnBr2 Lewis structure. Four electrons are shown as dots in the ZnBr2 chemical structure, whereas two single bonds each contain two electrons. The outermost valence shell electrons of the ZnBr2 molecule are 4 + 12= 16 as a result of the calculation.

So far, we’ve used 16 of the ZnBr2 Lewis structure’s total eight outermost valence shell electrons.

Complete the middle Zinc atom stability and, if necessary, apply a covalent bond. The core atom in the ZnBr2 Lewis structure is Zinc, which is bonded to the bromine atoms by two single bonds (Zn-Br). With the help of two single bonds, it already shares four electrons. As a result, bromine follows the octet rule and has eight electrons surrounding it on the two terminals of ZnBr2.

How to calculate the formal charge in ZnBr2 Lewis Structure?

The formal charge on the ZnBr2 molecule’s Zinc central atom often corresponds to the actual charge on that Zinc central atom. In the following computation, the formal charge will be calculated on the central Zinc atom of the ZnBr2 Lewis dot structure.

To calculate the formal charge on the central Zinc atom of the ZnBr2 molecule by using the following formula:
The formal charge on the Zinc atom of ZnBr2 molecule= (V. E(Zn)– L.E(Zn – 1/2(B.E))
V.E (Zn) = Valence electron in Zinc atom of ZnBr2 molecule
L.E(Zn) = Lone pairs of an electron in the Zinc atom of the ZnBr2 molecule.
B.E = Bond pair electron in Be atom of ZnBr2 molecule
calculation of formal charge on Zinc atom in ZnBr2 molecule

The Zinc core atom (two single bonds connected to bromines) of the ZnBr2 molecule has two valence electrons, zero lone pair electrons, and four bonding electrons. Put these values for the Zinc atom in the formula above.

Formal charge on Zinc atom of ZnBr2 molecule = (2- 0-(4/2)) =0

In the Lewis structure of ZnBr2, the formal charge on the central Zinc atom is zero.

Summary:

In this post, we discussed the method to construct the ZnBr2 Lewis structure. Need to remember that, if you follow the above-said method, you can construct molecular dot structure very easily.