Elements

Substances

A pure form of matter  which is homogeneous and cannot be separated by physical method.

Element

The  simplest form of matter which cannot be broken down into simplest form or substance.

For example

Hydrogen (H)

Chlorine (CI₂)

Oxygen  (O₂)  etc.

The 118 elements were known. Out of these 92 elements occur naturally.

26 elements prepared artificially.

Symbol

A short hand notation has represent the name of an element.

              Classification of elements

Elements are classified into three groups.

Metals

Non-Metals

Metalloids

Metals: 
            Metals are good conductor of heat and electricity and also have a shiny surface and are usually solid.

Non-Metals:
                    They have a dull surface and bad conductor of heat and electricity.

Metalloids:

                       They have both properties of metals as well as non-metals.