Theory:

The elements in the periodic table are classified as metals and non-metals based on their physical and chemical properties. There are around \(95\) metals and \(17\) non-metals in the periodic table.
Metals are electropositive elements where they donate electrons to form a stable configuration.
Physical properties of Metals:
A physical property can be observed and measured without altering the sample's chemical identity. In other words, a physical property can cause a physical change but not a chemical change.
 
Let us see some of the physical properties of metals:
  • State
  • Lustre
  • Malleability
  • Ductility
  • Hardness
  • Valency
  • Conduction
  • Density
  • Sonorous
  • Melting point and boiling point
State:
  
Most of the metals are solid at room temperature except mercury which is liquid at room temperature.
 
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Gold and silver
  
Lustre:
 
Metals are lustrous (shining or the reflecting nature of metals) in nature. For example gold and silver.
 
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Gold
 
Malleability:
  
Metals are malleable (as they can be drawn into thin sheets) in nature.
  
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Thin sheet of metals
  
Ductility:
  
Metals are ductile (as they can be drawn into wires) in nature.
 
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Ductility
 
Hardness:
  
All metals are hard except sodium and potassium.
 
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Hardness of metal
  
Valency:
  
Metals have \(1\) to \(3\) electrons in the outermost shell.
  
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Electron configuration of sodium metals
 
Conduction:
 
Metals are good conductors of heat and electricity (they have free electrons in their outermost shell).
 
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Conduction in metals
 
Density:
  
Metals have a high density (mass of a unit volume of a material substance).
  
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High density of metals
 
Sonorous:
 
Metals are sonorous (they produce a ringing sound when struck hard) in nature.
 
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Metal bell
  
Melting and Boiling Points:
  
Metals have high melting and boiling points because of their strong metallic bonds, except sodium and potassium, which have low melting and boiling points. 
 
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Gold on melting
The materials which generally possess the above properties are called Metals.
Example:
Iron, copper, aluminium, calcium, magnesium, gold, silver etc.