Question
Question: How many metals and non-metals are known?...
How many metals and non-metals are known?
Solution
Elements are arranged in a tabular form called periodic table and there are 115 elements present in the periodic table. There are similarities as well as differences in the properties of these elements. On the basis of these properties elements can be divided into metals and non-metals.
Complete step by step answer:
The elements which show the properties of metal are kept in the category of metals. The main physical properties followed by metals are:
1. Metals are lustrous in nature.
2. They show malleability and ductility.
3. Sonorous in nature.
4. Good conductor of heat and electricity.
5. Generally solid at room temperature.
6. High melting and boiling point.
Metals are arranged on the left side of the periodic table and there are five kinds of metals:
Alkaline earth metals, Alkali metals, Transition metals, Actinides and Lanthanides. There are a total 92 elements out of which 70 are metals.
While non-metal elements are those that do not possess the properties of metal. The number of non-metals on the periodic table is very less as compared to metals and these are arranged on the left side of the periodic table. Non-metals follows these properties:
1. Non-metals are brittle and soft in nature.
2. These are insulators.
3. They do show the properties shown by metals for example malleability, ductility etc.
And there are 22 non-metals in the periodic table.
Hence 70 metals and 22 non-metals are known to us.
Note: Rather than physical properties there are also some chemical properties on which we can distinguish metals and non-metals. There is one advantage of non-metals over metal that it cannot be easily corroded while metals readily get oxidized due to this they get corroded.