Materials: Metals and Non- Metals - Chapter Wise CBSE Solved Question and Answer Based On NCERT
Points To Remember:
There are 92 elements occurring naturally, out of which 70 are metals and about 22 are non- metals some elements show properties of both metals and non-metals they are called metalloids
Metals are solid, hard, malleable and ductile
Metals have high melting and boiling points and are good conductor of heat and electricity.
Non-metals may be solid, liquid or gas, and are not malleable and ductile.
Non- metals have low melting and boiling points and poor conductor of heat and electricity
Metals are sonorous
Metals react with acids to produce metal salts and hydrogen gas, generally non- metals do not react with acids
Some of the metals react with bases to produce hydrogen gas.
In aqueous solution less reactive metals are displaced by more reactive metals
Metals react with eater to produce metal hydroxides and hydrogen gas,non-metals do not react with water
Metals like gold, silver, platinum etc. retain their lustre because they do not react with air, water or acids. So they are called noble metals.
Both metals and non-metals are used widely in our day to day life
