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4.6 Other Bonds
Metallic Bond :
In metals, the atoms are linked by a special type of bond called ’metallic bond’. It is suggested that the atoms in a metal free some of their electrons and become positive ions. The matrix of positive ions remains embedded in a sea of mobile electrons. The free electrons really cement the positive metal ions and explain why metals are highly conductive of heat or electricity.
Hydrogen Bond :
Hydrogen atoms occuring in certain groups such as -OH carry some positive charge and are thus attracted to electronegative atoms like oxygen and nitrogen thereby making a link, called hydrogen bond, between two oxygen or nitrogen atoms.
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This hydrogen bond is electrostatic in nature and is not
very strong. In ice crystals we have a tetrahedral structure, each
oxygen atom is surrounded by four hydrogen atoms at the corner of
the tetrahedron. Two of these are covalently bond and other two form
a hydrogen bond.
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Van der Waal’s forces
These forces are the same as those existing between molecules in a real gas leading to its non-ideality. The forces are really interatomic or intermolecular, originating from dipole character. The forces are essentially weak. They exist between lattice layers of graphite or mica, as also between chains of selenium and tellurium.
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Index
4.1
Introduction
4.2 The Ionic Bonds
4.3 The Covalent Bonds
4.4 The Polar Bonds
4.5 Electronegativity
4.6 Others Bonds
Chapter 5
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