Question 1 Name one non-metal which conduct electricity?
Question 2 Name one non-metal which have shiny surface?
Question 3 Name one non-metal which is hard?
Question 4 Name one non-metal having high melting point?
Question 5 Why graphite is used in making electrodes?
Question 6 Name one non-metal which is brittle?
Question 7 Name one non-metal which has low melting point?
Non-Metals
For Example: Carbon, sulphur, phosphorus, silicon, hydrogen, oxygen, chlorine, bromine, iodine, helium etc.
Non-Metals are elements which form negative ions by gaining electrons. They are known as electronegative elements because they can form negative ions by gaining electrons.
There are 22 non-metals.
1) 10 solids
2) 1 liquid (bromine)
3) 11 gases
Physical Properties of Metals
1) Non-metals are not malleable and non-ductile.
They can neither be hammered into thin sheets nor drawn into thin wire.
They are brittle means break into pieces when hammered or stretched.
For Example :Sulphur, phosphorus.
2) They do not conduct heat and electricity
This is because they have no free electrons.
C (in the form of graphite) is the only non-metal which is a good conductor of heat and electricity and therefore it is used in making electrodes.
3) They are not lustrous: They are dull.
Iodine is the only non-metal which is lustrous.
4) They are generally soft except diamond (hard)
5) They are not strong: They can be easily broken.
6) Non-metals are solid, liquid or gases at the room temperature.
Carbon, Sulphur, Phosphorus are solid.
Bromine is a liquid.
Hydrogen, oxygen, nitrogen and chlorine are liquid.
7) They have low melting and boiling point except diamond.
8) They are non-sonorous.
9) They have low densities.
10) They have different colours.