Is Matter Around us Pure?

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08 Types of Elements

CLASSIFICATION OF ELEMENTS

All the elements can be divided into three groups:

Metals,
Non-metals, and
Metalloids

Metals:

A metal is an element that is malleable and ductile, and conducts electricity.
The examples of metals are iron, Copper, Aluminium, Zinc, Silver, Gold, Platinum, Magnesium, Nickel, Cobalt, Tin, Lead, Cadmium, Mercury, Antimony, Tungsten, Manganese and Uranium.
All the metals are solids, except mercury which is a liquid.

Properties of Metals:

Metals are malleable.
Metals are ductile.
Metals are good conductors of heat and electricity.
Metals are lustrous and can be polished.
Metals are generally hard except sodium and potassium which are soft metals.
Metals are usually strong. They have high tensile strength.
Metals are solids at the room temperature except mercury which is a liquid metal.
Metals generally have high melting points and boiling points.
Metals have high densities.
Metals are sonorous.
Metals usually have a silver or grey colour except copper and gold.

Non-metals:

A non-metal is an element that is neither malleable nor ductile, and does not conduct electricity. The examples of non-metals are Carbon, Sulphur, Phosphorus, etc.

Properties of Non-Metals:

Non-Metals are not malleable.
Non-metals are brittle.
Non-Metals are not ductile.
Non-Metals are bad conductors of heat and electricity.
Non-Metals are not lustrous and shiny). They are dull in appearance.
Non-Metals are generally soft except diamond which is an extremely hard non-metal.
Non-Metals are not strong. They have low tensile strength.
Non-Metals may be solid, liquid or gases at the room temperature.
Non-Metals have comparatively low melting points and boiling points except graphite which is a non-metal having a very high melting point.
Non-Metals have low densities.
Non-Metals are not sonorous.
Non-Metals have many different colours.

Comparison among the Properties of Metals and Non-Metals:

Metals	Non-Metals
Metals are malleable and ductile. They can be hammered into thin sheets and drawn into thin wires.	Non-metals are brittle. They are neither malleable nor ductile.
Metals are good conductors of heat and electricity.	Non-metals are bad conductors of heat and electricity. Exception: diamond, graphite
Metals are lustrous and shiny and can be polished.	Non-metals are non-lustrous and dull and cannot be polished. Exception: iodine
Metals are solids at room temperature Exception: mercury	Non-metals may be solid, liquid or gases at the room temperature.
Metals are strong and tough. They have high tensile strength.	Non-metals are not strong. They have low tensile strength.
Metals are sonorous. They make a ringing sound when struck.	6. Non-metals are not sonorous.

Metalloids:

Some properties of metals and some other properties of non-metals are called metalloids.
The important examples of metalloids are Boron (b), Silicon (Si), and Germanium (Ge).