Chemical Bonding and Molecular Structure

What is Chemical Bonding and Molecular Structure?

Chemical bonding is the process of interaction between atoms that leads to the formation of molecules or crystals. This interaction can be covalent, ionic, or metallic. Covalent bonding is the sharing of electrons between two atoms, ionic bonding is the transfer of electrons between atoms, and metallic bonding is the sharing of electrons between atoms in a metal.

Molecular structure is the arrangement of atoms in a molecule. This arrangement can be determined by studying the chemical bonding between the atoms. The most common molecular structure is the linear structure, in which the atoms are arranged in a line. However, molecules can also have a three-dimensional structure, in which the atoms are arranged in a three-dimensional shape.

Kossel – Lewis Approach to Chemical Bonding

The Kossel – Lewis approach to chemical bonding is a model that explains how atoms form chemical bonds to create molecules. The approach is based on the idea that atoms share electrons to form a stable electron configuration. The Kossel – Lewis approach can be used to explain the structure of molecules and the nature of chemical bonds.

Factors Which Affect the Formation of Ionic Bond –

The factors which affect the formation of ionic bond are as follows:

1. The size of the atom

The size of the atom affects the formation of ionic bond. The larger the atom, the more easily it can lose electrons to form a positively charged ion (cation). The smaller the atom, the more difficult it is to lose electrons and form a positively charged ion.

2. The charge of the atom

The charge of the atom affects the formation of ionic bond. The more negative the charge of the atom, the more easily it can lose electrons to form a positively charged ion (cation). The less negative the charge of the atom, the more difficult it is to lose electrons and form a positively charged ion.

3. The electronegativity of the atom

The electronegativity of the atom affects the formation of ionic bond. The more electronegative the atom, the more it attracts electrons to itself. The less electronegative the atom, the less it attracts electrons to itself.

4. The presence of a negatively charged atom

The presence of a negatively charged atom affects the formation of ionic bond. The negatively charged atom will attract the positively charged ions (cation) to itself. This will help to form the ionic bond.

Characteristics of Ionic Compounds –

Ionic compounds are typically formed when a metal and a non-metal combine. The metal donates electrons to the non-metal, and the two atoms become ions. Ionic compounds always have a positive and a negative ion. The positive ion is called the cation, and the negative ion is called the anion. Ionic compounds are held together by electrostatic forces, and they are typically very stable. Ionic compounds are hard and brittle, and they are often good conductors of electricity.

Lewis Structure of CO3-2 Ion –

The carbonate ion has a trigonal planar molecular geometry with an O-C-O bond angle of 120 degrees. The carbonate ion is a linear molecule with C-O-C bond angle of 180 degrees.

Bond Parameters

The bond parameters are:

Bond_length = 1.524 Å
Bond_angle = 109.5°

Bond_angle is 109.5 degrees because the bond between the two oxygen atoms is a double bond. This means that the atoms are sharing two pairs of electrons and are oriented at an angle of 109.5 degrees to each other.

Bond_length is 1.524 Å because the bond between the two oxygen atoms is a single bond. This means that the atoms are sharing one pair of electrons and are oriented at a distance of 1.524 Å to each other.

Factors Affecting Bond Length

The length of a bond is determined by the atomic radius of the atom that is bonded to the other atom and the electron affinity of the atom.

Factors Affecting Bond Energy –

The strength of a covalent bond between two atoms is determined by a number of factors. The most important factors are the electronegativity of the atoms involved and the distance between them.

The electronegativity of an atom is a measure of how strongly it attracts electrons to itself. The higher the electronegativity of an atom, the more it will pull electrons away from other atoms. This will make the bond between them weaker.

The distance between two atoms affects the strength of the bond between them. The closer the atoms are to each other, the stronger the bond will be. This is because the electrons are shared more evenly between the atoms when they are closer together.

The Valence Shell Electron Pair Repulsion (VSEPR) Theory

The VSEPR theory is a model that helps to predict the shapes of molecules. It is based on the idea that the electron pairs in a molecule will try to minimize their electrostatic repulsion (or interaction) with each other.

The shapes of molecules are determined by the number of electron pairs around the central atom and the distance between these electron pairs. The VSEPR theory can be used to predict the shapes of molecules, based on the number of electron pairs and the distance between them.

The following table summarizes the shapes of molecules, based on the number of electron pairs and the distance between them.

Number of electron pairs

Shape

1

Linear

2

Bent

3

T-shaped

4

Square

5

Pentagonal

6

Hexagonal

Decreasing Order of the Repulsive Interaction of Electron Pairs –

The order of the repulsive interaction of electron pairs decreases as the distance between the electron pairs decreases. This is because the repulsive interaction is a function of the distance between the electron pairs.

Valence Bond Theory

Valence bond theory is a theory of chemical bonding that considers covalent bonding to arise from the overlap of atomic orbitals. In simple terms, it states that atoms share electrons in order to fill their outermost shells.

Hybridization

Hybridization is the process of breeding different varieties of plants or animals to create a new, more desirable variety. For example, if you wanted to create a new type of apple that was both sweet and tart, you could breed two different types of apples together.

The Main Features of Hybridization Are As Follows –

1. The combination of two different species to create a new, third species.

2. The offspring of the two different species are usually more fit than either of their parents.

3. Hybrids are often more fertile than either of their parents.

4. Hybrids are usually more variable than either of their parents.

Conditions for Hybridization –

The two species must be able to produce viable offspring.

The two species must be able to mate.

The two species must share a common ancestor.

Types of Hybridization –

There are three types of hybridization:

1. Point hybridization
2. Molecular hybridization
3. Structural hybridization

Molecular Orbital Theory

The molecular orbital theory is a theory that explains how electrons are distributed in molecules. The theory is based on the assumption that the electrons in a molecule are not localized in any specific region of space, but are instead distributed evenly throughout the molecule. This distribution of electrons is called a molecular orbital.

There are two types of molecular orbitals: bonding orbitals and antibonding orbitals. Bonding orbitals are orbitals that contain electrons that are shared between two atoms. Antibonding orbitals are orbitals that contain electrons that are not shared between atoms. Antibonding orbitals are important because they help to stabilize molecules by preventing them from breaking apart.

Hydrogen Bonding

A hydrogen bond is a type of intermolecular force that is responsible for the attractions between polar molecules. Polar molecules have a partially positive and partially negative end, and these ends are attracted to each other through hydrogen bonding.

Types of Hydrogen Bonding –

There are three types of hydrogen bonding, which are:

Ionic hydrogen bonding

Covalent hydrogen bonding

Metallic hydrogen bonding

The Chemical Bond’s General Structure

In terms of its general structure, a chemical bond is formed when two atoms share one or more pairs of electrons.

How can You prepare for the Chapter of Chemical Bonding?

In order to prepare for the chapter of chemical bonding, it is important to understand the basics of atoms and molecules. Additionally, one should be familiar with the types of chemical bonding that can occur between atoms and molecules.