LEARNATHON
III

Competition for grade 6 to 10 students! Learn, solve tests and earn prizes!

### 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's see some of the physical properties of metals.
• State
• Lustre
• Malleability
• Ductility
• Hardness
• Valency
• Conduction
• Density
• Sonorous
• Melting and Boiling Points
State:

Most of the metals are solid at room temperature, except mercury which is liquid at room temperature.

Lustre:

Metals are lustrous in nature (shining or the reflecting nature of metals), such as gold and silver.

Malleability:

Metals are malleable in nature (as they can be drawn into thin sheets).

Ductility:

Metals are ductile in nature (as they can be drawn into wires).

Hardness:

All metals are hard except sodium and potassium.

Valency:

Metals have $$1$$ to $$3$$ electrons in the outermost shell.

Conduction:

Metals are good conductors of heat and electricity (they have free electrons in their outermost shell).

Density:

Metals have a high density (mass of unit volume of a material substance).

Sonorous:

Metals are sonorous in nature (they produce a ringing sound when struck hard).

Melting and Boiling Points:

Metals have high melting and boiling points because of their strong metallic bonds, except for sodium and potassium, which has a low melting and boiling points.
The materials which generally possess the above properties are called Metals.
Example:
Iron, copper, aluminium, calcium, magnesium, gold, silver etc.