Page 1 - 3. Lesson notes - Ch-3 Covalent Bonding

SAI International School
Class-X

Subject_ Chemistry
Topic-Metal & Non metals
Subtopic- Chemical Bonding (Covalent Bonding)

LESSON NOTES

➢ Chemical bond:

• A chemical bond is a lasting attraction between atoms, ions or molecules
that enables the formation of chemical compounds.

• The bond may result from the electrostatic force of attraction between
oppositely charged ions as in ionic bonds or through the sharing of electrons
as in covalent bond.

Chemical Bonds may be of two types-

Ionic Bonds Covalent Bonds

1.Formed by the reaction of a metal 1.Formed by the reaction of two non-
with a non metal metals with each other.

2.By transfer of electrons from metal 2. By sharing of electrons between
to non metallic atom. the two non-metallic atoms.

3.Formation of +ve ions & -ve ions takes 3. Formation of molecules takes
place. place.

• Covalent Bonds-
 A covalent bond is a chemical bond that involves the sharing of electron
pairs between non- metallic atoms.

 These electron pairs are known as shared pairs or bond pairs, as
these shared pair of electrons form a covalent bond.

 A filled up outer shell usually has eight electrons, [or two in the case of
hydrogen or helium] and is known as a stable configuration since it is similar to
the nearest Noble Gas configuration.

 Hence atoms of all elements strive to attain stability by attaining a

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