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Concise Selina Solutions for Class 9 Chemistry Chapter 4 Atomic Structure and Chemical Bonding


A single covalent bond is formed by sharing of one pair of electrons between atoms, each atom contributing one electron. A double bond is formed by sharing two pairs of electrons between two atoms. A triple bond is formed by sharing of three pairs of electrons between two atoms. Atoms are minute particles that are found in every object. Various atomic models were devised by several scientists to describe the atomic structure.

Thomson’s model states that an atom comprises a positively charged sphere with electrons embedded in it.

Rutherford’s model states that the centre of the atom has positively charged nucleus and negatively charged electrons rotate around the nucleus.

Neil Bohr’s model states that the electrons revolve around the nucleus at distinct orbits without any energy loss.

ICSE solutions provided here sheds light on the structure of an atom, mass number, atomic number, Octet rule. This solution helps you to understand constituents of atoms, electron distribution in orbits, electrovalent and covalent bonding.