Home Preparation for National Talent Search Examination (NTSE)/ Olympiad
Chapter : 2. Elementary Idea of Bonding
Points to Remember
♦ A chemical bond is the force of attraction which holds together the atoms in a molecule. ♦ An electrovalent bond is formed as a result of complete transfer of electron(s) from one atom to another. ♦ Atoms which can lose electrons and form positive ions are said to be electropositive. ♦ Atoms which can gain electrons and form negative ions are said to be electronegative. ♦ The total number of electrons lost or gained by an atom to attain the stable configuration of the nearest noble gas is known as the valency of the atom. ♦ The number of electrovalent bonds an atom can form is called its electrovalency. ♦ Covalent bonds are formed by the mutual sharing of electrons between the combining atoms. ♦ Compounds containing covalent bonds are called covalent compounds. ♦ The total number of electrons shared by a given atom in the formation of covalent bonds to attain the stable configuration of its nearest noble gas is known as its covalency. ♦ The force that holds the atoms closely together in a metal is known as the metallic bond.