The attractive forces which holds various constituents such as atoms molecules and ions together in different chemical species is called a covalent bond A covalent bond includes the sharing of electrons between two atoms. 4] Classification Based on Molecular Forces. CHEMICAL BONDING AND MOLECULAR STRUCTURE 101 4.1 KÖSSEL-LEWIS APPROACH TO CHEMICAL BONDING In order to explain the for mation of chemical bond in terms of electrons, a number of attempts were made, but it was only in 1916 when Kössel and Lewis succeeded independently in giving a satisfactory explanation. endstream endobj startxref Chemical Bonding and Molecular Structure ... Hydrogen bonding in Kevlar, a strong polymer used in bullet-proof vests. h�bbd``b`z$�C3�`y$8�@bN@��$� $�8��� endstream endobj 94 0 obj <> endobj 95 0 obj <> endobj 96 0 obj <>stream This is called octet rule. Primary Bonds ... Bonds Found in Polymers Induction Forces are intermolecular forces exist between the permanent and induced dipole. 5.5 INTERMOLECULAR FORCES A molecule is a group of atoms connected by covalent bonds. The revision notes help you revise the whole chapter in minutes. As food and beverages require more and more green and safe packaging products, the emergence of polymer coated steel (PCS) has been promoted. The common examples are nylon-66, dacron, and silk. 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A polymer (/ ˈ p ɒ l ɪ m ər /; Greek poly-, "many" + -mer, "part") is a substance or material consisting of very large molecules, or macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. These are the Chemical Bonding and Molecular Structure class 11 Notes Chemistry prepared by team of expert teachers. Except for noble gases, no other elements occur independently. A hydrogen bond is the attraction between the lone pair of an electronegative atom and a hydrogen atom that is bonded to an electronegative atom, usually nitrogen, oxygen, or fluorine. large molecule or a macromolecule which essentially is a combination of many subunits link is a chemical bond between polymer chains other than at the ends. Simulation methods 2.1. Induction forces are weak and temperature independent. metallic oxides, this is hardly the case : polymers have a poor wettability 1 POLYMERS Polymers are the high molecular weight compounds obtained by repeated union of simple molecules. Larger molecules generally are more polarizable, so large polymers with high molecular weights can have significant dispersion forces. Download revision notes for Chemical Bonding and Molecular Structure class 11 Notes Chemistry and score high in exams. (Monomers). Chemical bonding and molecular structure 1) Explain the formation of a chemical bond. trailer %%EOF These polymers can be drawn into long, thin and thread like fibres and therefore can be woven into fabrics. The term polymer is defined as very large molecules having high molecular mass. Intramolecular forces are the forces that hold atoms together within a molecule. 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