Metals and Properties that an element to be considered as metal

A Metal may be described as a material which is solid at room temperature, has relatively high density, high melting temperature and low specific heat, good electrical and thermal conductivity, strength and hardness, etc. Most metals are elastic to limit; they deform in proportion to stress and return to the original state when the stress is released. At higher stresses they deform plastically. Some metal will accept a deal of plastic deformation before failure.

A metal can exist in the gaseous, liquid and solid states. The state depends on the pressure exerted on the metal and on its temperature.

Some of the properties that an element must have to be considered as a metal are :

1. Ability to donate electrons and form a positive ion.

2. Crystalline structure.

3. High thermal and electrical conductivity.

4. Metallic luster.

5. Ability to be deformed plastically.

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Mechinopedia For Mechanical Engineers

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