An element is a substance which cannot be split into two or more simpler substance by chemical reaction.
Every element is given a name and a chemical symbol
Elements
109 types of element have been discovered so far.
92 element occur naturally while the rest are man-made
Most element are found combined with other elements in the form of ores or minerals
This is the Periodic Table
Each vertical column is called a groupThey have similar chemical properties. Each group has its own unique properties.
Each horizontal row is called a period
Elements in a period from left to right shows a gradual change from metallic preperties to non-metallic properties
In the periodic table, each element is represented by chemical symbol.
For e.g., Aluminium is called Al
Zinc is called Zn
Magnesium is called Mg
Element can be classified into Metals, and Non-metals
Properties of Metallic and Non-metallic Elements
Metallic element has high melting point and boiling point.
They are good heat and electrical conductors.
They are ductile and malleable.
They are shiny, has high densities and sonorous.
Non-metallic elements have low melting and boiling points.
They are poor heat and electrical conductors except graphite.
They are brittle
They are dull in appearance, has low densities and are not sonorous.
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