How to draw H2Se Lewis Structure? - Science Education and Tutorials

Q: What is the H2Se Lewis structure?

H2S e Lewis structure is dot representation

Q: What is the formal charge on the H2Se Lewis structure?

Zero charges on the H2S e molecular structure

The hydrogen selenide chemical formula is H2Se. Drawing H2Se Lewis Structure is very easy to by using the following method. Here in this post, we described step by step method to construct H2Se Lewis Structure. The selenium and hydrogen elements come as members of the oxygen and hydrogen family groups from the periodic table respectively. The valence electrons in selenium and hydrogen are six and one respectively. Hydrogen selenide is used to make chemical reagents for organic chemical reactions for the production of selenium-organic materials.

Table of Contents

Key Points To Consider When Drawing The H2Se Electron Dot Structure

A three-step approach for drawing the H2Se Lewis structure can be used. The first step is to sketch the Lewis structure of the H2Se molecule, to add valence electrons around the selenium atom; the second step is to add valence electrons to the two hydrogen atoms, and the final step is to combine the step1 and step2 to get the H2Se Lewis Structure.

The H2Se Lewis structure is a diagram that illustrates the number of valence electrons and bond electron pairs in the H2Se molecule. The geometry of the H2Se molecule can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory), which states that molecules will choose the H2Se geometrical shape in which the electrons have from one another.

Finally, you must add their bond polarities to compute the strength of the two Se-H single bonds (dipole moment properties of the H2Se molecule). The selenium-hydrogen bonds in hydrogen selenide(H2Se), for example, are polarised toward the more electronegative selenium in H2Se molecule, and because both bonds have the same size and are located around two hydrogen terminals of the tetrahedral or bent V-shaped with two lone pairs (in total four electrons) on the selenium atom, their sum of dipole moment is nonzero due to the H2Se molecule’s bond dipole moment and less electron polarity to the hydrogen atoms. Because each two Se-H bonds polarity not canceled each other in the H2Se molecule due to the presence of two lone pairs of electrons. The hydrogen selenide(H2Se) molecule is classified as a polar molecule.

The molecule of hydrogen selenide (with tetrahedral or bent V-shaped molecular geometry) is tilted, the bond angles between selenium and hydrogen are 92 degrees. It has a difference in electronegativity values between selenium and hydrogen atoms, with central selenium’s pull being higher than terminal hydrogen’s in the H2Se molecule. But they do not cancel each other due to the asymmetrical tetrahedral with two lone pairs in the molecular geometry of the H2Se molecule.

As a result, it has the nonzero dipole moment. The H2Se molecule has a nonzero dipole moment due to an unequal charge distribution of negative and positive charges. But both selenium and hydrogen atoms fall on the oxygen and hydrogen family groups in the periodic table respectively. The selenium atom is a more electronegative value than hydrogen in the H2Se molecule. The H2Se molecule has the net dipole moment of 0.95D value in the ground state energy level.

H2Se molecule has two Se-H single bonds. 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 H2Se 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: H2Se Lewis Structure

The central atom is selenium, which is bordered on two terminals with hydrogen atoms( in tetrahedral geometry), and two lone pairs on the central selenium atom in the tetrahedral molecular geometry. selenium has six outermost valence electrons, indicating that it possesses six electrons in its outermost shell, whereas hydrogen also has one valence electron in its outermost shell. To complete the octet of the selenium atom requires two valence electrons on each of their outermost shell.

Two hydrogen atoms establish covalent connections with the central selenium atom as a result, leaving the selenium atom with two lone pairs. There are two lone pairs of electrons on the selenium central atom that resists the bond pairs of the two Se-H bonds. According to VSEPR theory, the single Se-H bond pairs polarity lead the H2Se molecule to take on the tetrahedral geometry structure.

The H2Se molecule’s two Se-H bonds are arranged in symmetrical polarity order around the tetrahedral molecular geometry, giving rise to the H2Se molecular shape. The H2Se molecule has a tetrahedral or V-shaped bent molecular geometry because there is an electrical repulsion between the lone pairs of electrons in selenium and two single bond pairs(Se-H) of the H2Se molecule.

Lewis structure of H2Se has dot electron representative structure. Valence electrons of atoms undergo orbitals mixing in the chemical reactions, giving new types of molecular species of H2Se. 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 H2Se Molecule:

selenium and hydrogen Electronegative difference in H2Se:

The selenium atom has an electronegativity of 2.58, while hydrogen has an electronegativity of 2.2 in the H2Se molecule. The difference in electronegativity of selenium and hydrogen can be estimated using the method below.

The electronegative value difference between selenium and hydrogen in H2Se molecule
Electronegativity value of selenium = 2.55
Electronegativity value of hydrogen= 2.20
Difference of electronegativity value between selenium and hydrogen in H2Se molecule = 2.55 – 2.20 = 0.35
Electronegativity difference between Se-H bond calculation of H2Se molecule

The electronegative difference between selenium and hydrogen is less than 0.5. This indicated the bond polarity moves near to nonpolar nature. H-Se bond polarity in the H2Se molecule is nonpolar.

Because of this difference in electronegativity of selenium and hydrogen atoms, the H2Se molecule’s Se-H bond becomes nonpolar. The total net dipole moment of the H2Se molecule is nonzero due to the noncancellation of the bond dipole moment in the tetrahedral geometry due to the presence of two 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 H2Se is discussed in our previous post.

As a result, the Se-H bond’s dipole moment is less due to the polarization of the bonds and two lone pairs of electrons on selenium, and all Se-H bonds’ dipoles are arranged in the asymmetrical H2Se molecular geometry. The H2Se molecule has a nonzero net dipole moment.

The electron dot structure of the H2Se molecule is also known as the H2Se Lewis structure. It determines the number of outermost valence electrons as well as the electrons engaged in the H2Se molecule’s bond formation. The outermost valence electrons of the H2Se molecule must be understood while constructing the Lewis structure of the molecule.

The selenium atom is the middle element in H2Se molecular geometry, with six electrons in its outermost valence electron shell, whereas the hydrogen atom has one electron in its outermost valence electron shell. The hydrogen atom has one valence electron.

The H2Se has a total of 8 valence electrons as a result of the foregoing above-said reasoning. With the core central selenium atom, the two terminals with two hydrogen atoms form covalent bonds, leaving the selenium atom with two lone pairs in the middle of tetrahedral geometry.

Because no lone pairs on the terminal hydrogen atoms create interaction with Se-H bond pairs(but it is negligible in the ground state of the H2Se molecule). The bond angle of the H-Se-H bond in the tetrahedral molecular geometry is approximately 92 degrees. This angle is less than the CH4 molecule bond angle. The Se-H bond length is 134pm(picometer).

To sketch the H2Se Lewis structure by following these instructions:

Step-1: H2Se Lewis dot Structure by counting valence electrons on the selenium atom

To calculate the valence electron of each atom in H2Se, look for its periodic group from the periodic table. The oxygen and hydrogen group families, which are the 16th and 1st groups in the periodic table, are both made up of selenium and hydrogen atoms respectively. In their outermost shells, hydrogen and selenium have one and six valence electrons respectively.

Calculate the total number of valence electrons in the H2Se molecule’s outermost valence shell. The first step is to determine how many electrons are in the H2Se 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 H2Se Lewis diagram. The H2Se molecule’s core selenium atom can be represented as follows:

Total outermost valence shell electron of selenium atom in H2Se= 6
Total outermost valence shell electron of hydrogen atom in H2Se= 1
The H2Se molecule has one central selenium and two hydrogen atoms. Then the total outermost valence shell electrons can be calculated as follows
∴ Total outermost valence shell electrons available for H2Se Lewis structure( dot structure) = 6+2*2= 8 valence electrons in H2Se.
calculation of total valence electron of H2Se molecule

Choose the atom with the least electronegative value atom and insert it in the center of the molecular geometry of H2Se. We’ll choose the least electronegative value atom in the H2Se molecule to place in the center of the H2Se Lewis structure diagram in this phase.

But in this case, hydrogen is the least electronegative than selenium. Hydrogen takes a maximum of two-electron in its orbital. This gives hydride ion(H-). So that selenium stays in the central molecular structure. The electronegativity value in periodic groups grows from left to right in the periodic table and drops from top to bottom.

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

Step-2: Lewis Structure of H2Se for counting valence electrons around the terminal hydrogen atoms

As a result, selenium is the third atom in the periodic table’s oxygen family group. Hydrogen is the first member of the hydrogen family. It is the first element in the periodic table. The electronegative value of the selenium atom is higher than that of the hydrogen atom in the H2Se molecule. Furthermore, hydrogen has a one-electron limit since it is the less electronegative element in the H2Se molecule.

In the H2Se Lewis structure diagram, the selenium atom can be the center atom of the molecule. As a result, central selenium in the H2Se Lewis structure, with all two hydrogen atoms arranged in a tetrahedral geometry.

Add valence electron around the hydrogen atom, as given in the figure.

Step-3: Lewis dot Structure for H2Se generated from step-1 and step-2

Connect the exterior and core central atom of the H2Se molecule with two single Se-H bonds. In this stage, use two hydrogen atoms on the outside of the H2Se molecule to the central selenium atom in the middle.

Count how many electrons from the outermost valence shell have been used in the H2Se structure so far. Each Se-H single bond carries two electrons because each selenium atom is connected to two hydrogen atoms by two Se-H single bonds. Bond pairings of Se-H are what they’re called.

So, out of the total of 8 valence electrons available for the H2Se Lewis structure, we used four electrons for the H2Se molecule’s two Se-H single bonds. The H2Se molecule has two lone pairs of electrons in the central selenium atom.

Place the valence electrons in the Se-H bond pairs starting with the core selenium, two hydrogen atoms in the H2Se molecule. In the H2Se Lewis structure diagram, we always begin by introducing valence electrons from the central selenium atom(in step1). As a result, wrap around the central selenium atom’s bond pair valence electrons first (see figure for step1).

The selenium atom in the molecule gets only 8 electrons around its molecular structure. This central selenium atom is octet stable. But it has two lone pairs.

Hydrogen molecule(H2) is in the gaseous state at normal temperature and pressure. It is used as a hydrogenating agent in the field of organic chemistry. It is highly flammable in nature. It is applied in fuel cells. During the combustion, hydrogen gas gives the stream as the final product. This reduces environmental pollution.

Selenium requires 8 electrons in its outermost valence shell to complete the molecular octet stability, 4 electrons bond pairs in two Se-H single bonds, and two lone pairs in the central selenium atom. No lone pairs of electrons on the hydrogen atoms of the H2Se molecule are placed in a tetrahedral geometry. Seleniumalready shares 8 electrons to the two Se-H single bonds. Then place the valence electron in the hydrogen atoms, it placed around one electron on each atom(step-2). There are no valence electrons placed around two hydrogen atoms as lone pair of electrons.

We’ve positioned 8 electrons around the two-terminal hydrogen atoms(step-3), which is represented by a dot, in the H2Se molecular structure above. The selenium atom completes its molecular octet stability in the H2Se molecule because it possesses 4 electrons in its (two Se-H single bonds) bond pairs with two hydrogens in the outermost valence shell.

Count how many outermost valence shell electrons have been used so far using the H2Se Lewis structure. Two electron bond pairs are shown as dots in the H2Se chemical structure, whereas two single bonds each contain two electrons. The outermost valence shell electrons of the H2Se molecule(bond pairs) are 4 as a result of the calculation. The total valence electron in a selenium atom is 8.

So far, we’ve used 8 of the H2Se Lewis structure’s total 8 outermost valence shell electrons. Two lone pairs of electrons on the selenium atom in the tetrahedral geometry of the H2Se molecule.

Complete the middle selenium atom stability and, if necessary, apply a covalent bond. The central selenium atom undergoes octet stability(due to two single bond pairs of electrons).

The core atom in the H2Se Lewis structure is selenium, which is bonded to the two hydrogen atoms by single bonds (two Se-H). With the help of two single bonds, it already shares 8 electrons. As a result, the selenium follows the octet rule and has 8 electrons surrounding it on the two terminals of the H2Se molecule’s tetrahedral geometry.

How to calculate the formal charge on selenium and hydrogen atoms in H2Se Lewis Structure?

Calculating formal charge on the selenium of H2Se molecule:

The formal charge on the H2Se molecule’s selenium central atom often corresponds to the actual charge on that selenium central atom. In the following computation, the formal charge will be calculated on the central selenium atom of the H2Se Lewis dot structure.

To calculate the formal charge on the central selenium atom of the H2Se molecule by using the following formula:
The formal charge on the selenium atom of H2Se molecule= (V. E(Se)– L.E(Se) – 1/2(B.E))
V.E (Se) = Valence electron in a selenium atom of H2Se molecule
L.E(Se) = Lone pairs of an electron in the selenium atom of the H2Se molecule.
B.E = Bond pair electron in Se atom of H2Se molecule
calculation of formal charge on selenium atom in H2Se molecule

The selenium core atom (two single bonds connected to two hydrogen atoms ) of the H2Se molecule has six valence electrons, two lone pairs of electrons(four electrons), and 4 bonding pairing valence electrons. Put these values for the selenium atom in the formula above.

Formal charge on selenium atom of H2Se molecule = (6- 4-(4/2)) =0

In the Lewis structure of H2Se, the formal charge on the central selenium atom is zero.

Calculating formal charge on the hydrogen atom of H2Se molecule:

The formal charge on the H2Se molecule’s hydrogen terminal atoms often corresponds to the actual charge on that hydrogen terminal atoms. In the following computation, the formal charge will be calculated on the terminal hydrogen atom of the H2Se Lewis dot structure.

To calculate the formal charge on the terminal hydrogen atom of the H2Se molecule by using the following formula:
The formal charge on the hydrogen atom of H2Se molecule= (V. E(H)– L.E(H) – 1/2(B.E))
V.E (H) = Valence electron in a hydrogen atom of H2Se molecule
L.E(H) = Lone pairs of an electron in the hydrogen atom of the H2Se molecule.
B.E = Bond pair electron in H atom of H2Se molecule
calculation of formal charge on hydrogen atom in H2Se molecule

The hydrogen terminal atoms of the H2Se molecule have one valence electron, no lone pairs of electrons(zero electrons), and two bonding pairing valence electrons(single bond). Put these values for the hydrogen atom in the formula above.

Formal charge on hydrogen atom of H2Se molecule = (1- 0-(2/2)) =0

In the Lewis structure of H2Se, the formal charge on the terminal hydrogen atom is zero.

Summary:

In this post, we discussed the method to construct the H2Se Lewis structure. First, the valence electrons are placed around the selenium atom. Second, place the valence electron on the hydrogen atoms. Finally, when we combined the first and second steps. It gives H2Se Lewis structure. Need to remember that, if you follow the above-said method, you can construct molecular dot structure very easily.