Whenever word bond to hear it means to tie something together and chemical means that is irreversible by the physical method.Chemical bonding is an attractive force which keeps two atoms or ions together in a molecule.During chemical bonding atoms attain stability in three different ways by losing or gaining electrons by sharing electrons.
Why do atoms form Chemical Bonding?
Atoms combine to form a bond to achieve minimum energy and maximum stability. These are the two key factors that tell why atoms combine to form a chemical bond.If the atom does not have minimum energy then it will never have stability so the bond is not possible.
Chemical bonds definition
During redistribution of electrons, a bond (force) of attraction develops between atoms, which binds them together to form molecules. This bond is known as the chemical bond.
A chemical bond may be defined as the force of attraction between any two atoms, in a molecule, to maintain stability.The attractive forces which hold various constituents (atoms, ions etc) together in different chemical species form chemical bonding.
Energy Release In Chemical Bonding
Atom is the smallest particle of an element which in most cases does not exist in the free state and has a tendency to combine with the atom(s) of other metal to form a molecule. This combined state of the atom is more stable than the free state.
When two atoms (similar or different) approach each other and combine to form a molecule, the resulting stable molecule always has less energy than the free atom(s) i.e. a combination of atom(s) to form a stable molecule always leads to decrease in energy of the system. For example,
Thus note that
(i) bond formation is an exothermic process.
(ii) bond formation between two atoms occurs only when there is an overall decrease in the energy of the system.
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Electronic theory of valency in Chemical Bonding
Essential features of the theory of electronic valency, as proposed by Kossel and Lewis are summed up below.
(i) Bond formation involves only electrons of the outermost shell of atoms of an element. However, in transition elements electrons of (n – 1) d sub-shell also participate in chemical bonding.
(ii) Every atom (except those of noble gases) has a tendency to acquire their nearest noble gas like configuration (i.e. 2 or 8 electrons) in the outermost shell. Actually, this tendency is responsible for the chemical reactivity of the elements.
(iii) Atom can acquire noble gas like configuration by losing, gaining or sharing of electrons with other atom(s).
(iv) The number of electrons lost, gained or shared by an atom of an element is known as its valency.
Examples of Chemical Bonds
There are three methods in which atoms can achieve a bond and a stable configuration.
(1) The transfer of one or more electrons from one atom to the other to form an electrovalent (or an ionic) bond.
(2) Sharing of one, two or three pairs of electrons between two atoms to form a covalent (or a molecular) bond.
(3) When the shared electron pairs are contributed by only one of the combining atoms, the bond formed is known as coordinate (or dative) bond.
Depth knowledge under following subtopics:
- Ionic and Covalent Bond.
- Ionic Bond Examples.
- Covalent Bond Examples.
- Polar And Non-Polar Covalent Bonds.
- Metallic Bond With types.
Elements participating in chemical bonding
Elements participate in chemical bond decide as follow:
1. Electropositive elements: – These are those atoms of element give up electrons easily, they have low ionization potentials.
2. Electronegative elements: – Atoms of the element which gain electrons. They have the higher value of electronegativity.
3. Few Elements have the little tendency to lose or gain electrons.
- When electropositive(metal) and electronegative(non-metal) element combine. They form an Ionic bond (electrovalent bond).
- When high electronegative and electronegative element combine. They form a Covalent bond.
- -OR-When electropositive and electronegative element combine. They form a Covalent bond.
- When electropositive and electropositive element combine. They form a Metallic bond.
Chemical Bonding Worksheet With Question- Answers
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This is about the Chemical Bonding