Class 10 Chemistry
Physical properties of non-metals
Hardness: Non-metals are not hard rather they are generally soft. But diamond is exception; it is most hard naturally occurring substance.
State: Non-metals may be solid, liquid or gas.
Lustre: Non-metals have dull appearance. Diamond and iodine are exceptions.
Sonority: Non-metals are not sonorous, i.e. they do not produce a typical sound no being hit.
Conduction: Non-metals are bad conductor of heat and electricity. Graphite which is allotrope of carbon is good conductor of electricity, and is an exception.
Malleability and ductility: Non-metals are brittle.
Melting and boiling point: Non-metals have generally low melting and boiling points.
Density: Most of the non-metals have low density.
Color: Non-metals are of many colors.
Chemical properties of Non-metals
Reaction of non-metals with oxygen: Non-metals form respective oxide when react with oxygen.
Non-metal + Oxygen ⇨ Non-metal oxide
When carbon reacts with oxygen, carbon dioxide is formed along with production of heat.
C + O2 ⇨ CO2 + Heat
When carbon is burnt in insufficient supply of air, it forms carbon monoxide. Carbon monoxide is a toxic substance. Inhaling of carbon monoxide may prove fatal.
2C + O2 ⇨ 2CO + Heat
Sulphur gives sulphur dioxide when react with oxygen. Sulphur caught fire when exposed to air.
S + O2 ⇨ SO2
When hydrogen reacts with oxygen it gives water.
2H2 + O2 ⇨ 2H2O
Non-metal oxides are acidic in nature. Solution of non-metal oxides turns blue litmus red.
Carbon dioxide gives carbonic acid when dissolved in water.
CO2 + H2O ⇨ H2CO3
Sulphur dioxide gives sulphurous acid when dissolved in water.
SO2 + H2O ⇨ H2SO3
Sulphur dioxide gives sulphur trioxide when it reacts with oxygen.
2SO2 + O2 ⇨ 2SO3
Sulphur trioxide gives sulphuric acid when dissolved in water.
SO3 + H2O ⇨ H2SO4