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ionic core of another atom. This collection of mobile free electrons around the ionic core is found to be more stable than the neutral atoms. The force between the mobile valence electrons and positive ionic cores holds the metallic atoms together, which is known as metallic bond. Properties: 1. Metallic compounds are usually solids. However, mercury
is the example of a liquid metallic compound. 2. Metallic compounds are usually crystalline in nature. 3. They are good conductors in solid state.
Metallic bonds are weak bonds.
Metallic bonds are non-directional. 6. Metallic compounds are opaque to light. This is because.
light energy falling on them is absorbed by mobile electrons. (બ) બધી ધાતુઓ સામાન્ય તાપમાન પર ઘન કે નક્કર સ્વરૂપમાં હોય
છે. (માત્ર પારો આ બાબતે અપવાદ છે.) નક્કર પદાર્થોમાં જે સ્ફટિક રુપ છે, એની વિશેષતાઓ આ રીતે બતાવવામાં આવી છે, એજન, ų. 9246. “Solids All solids have the property of elasticity and by virtue of this property, the solids behave as in compressible substances and exhibit rigidity and the mechanical strength. Basically, all solids are made of atoms and molecules but due to the different internal arrangement of the molecules inside them, they are divided into two classes, namely crystalline and amorphous materials. Crystalline Materials The crystalline materials are those in which atoms or molecules are arranged in a definite and regular way troughout the body of the crystal and possess a definite external geometrical shape. A few examples of crystalline substances are quartz, mica, sugar, copper sulphate, sodium chloride etc. The crystalline substances have the following characteristics : 1. The atoms or molecules constituting a crystalline solid are
arranged in a definite and regular manner inside the crystal. Due to this, crystalline materials have definite external
geometrical shape. 2. The orderly arrangement of atoms and molecules in a crystal
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