Chemistry
Non-metals
1. Explain with equations, the action of (i) oxygen, (ii) cone. Nitric acid, (iii)
chlorine, (iv) hydrogen on non – metals. Use carbon, sulphur, phosphorus and
nitrogen on examples.
(i) Reaction with oxygen: Non – metals like carbon and sulphur combine with oxygen
to form CO2 and SO2 respectively. These oxides dissolve in water to give carbonic acid
and sulphurous acid.
C + O2 CO2 (g)
CO2 (g) + H2O H2CO3
( Carbonic acid )
S + O2 SO2 (g)
SO2 (g) + H2O H2SO3
(sulphurous acid)
(ii) Reaction with nitric acid: Sulphur reacts with concentrated nirtric acid to form
H2SO4 and NO2.
S + 6HNO3 H2SO4 + 6NO2 (g) + 2H2O
(iii) Reaction with chlorine: Phosphorus and hydrogen reacts with chlorine to form
phosphorus trichloride and hydrogen chloride respectively.
P4 + 6Cl2 4 PCl3 (g)
H2 + Cl2 2 HCl (g)
(iv) Reaction with hydrogen:
Nitrogen reacts with hydrogen to give Ammonia.
N2 + 3H2 2 NH3
, 2. What happens when silicon is treated with (i) oxygen, (ii) chlorine, (iii) steam,
(iv) hydrochloric acid (v) sodium hydroxide.
(i) Reaction with oxygen: Silicon burns in the oxygen of air to form a white solid
compound called silicon dioxide (silica / sand).
Si + O2 SiO2
Silicon dioxide
(ii) Reaction with chlorine: On heating to a temperature of 450C, silicon combines
with chlorine to from silicon tetra chloride.
Heat
Si + 2Cl2 SiCl4
450C Silicon tetra chloride
(iii) Reaction with steam: Red hot silicon reacts with steam to form silicon dioxide
and hydrogen gas.
Heat
Si + 2H2 O SiO2 + 2H2
silicon steam Silicon hydrogen
(Red hot) dioxide
(iv) Reaction with Hydrochloric Acid: Silicon reacts with hydrochloric acid to form
silicon tetra chloride and hydrogen gas is liberated.
Si + 4HCl SiCl4 + 2H2
silicon hydrogen
tetrachloride
(iv) Reaction with sodium hydroxide: Silicon reacts with hot sodium hydroxide
solution to form sodium silicate with the evolution of hydrogen gas.
Si + 2NaOH + H2O Na2SiO3 + 2H2
sodium silicate hydrogen
Non-metals
1. Explain with equations, the action of (i) oxygen, (ii) cone. Nitric acid, (iii)
chlorine, (iv) hydrogen on non – metals. Use carbon, sulphur, phosphorus and
nitrogen on examples.
(i) Reaction with oxygen: Non – metals like carbon and sulphur combine with oxygen
to form CO2 and SO2 respectively. These oxides dissolve in water to give carbonic acid
and sulphurous acid.
C + O2 CO2 (g)
CO2 (g) + H2O H2CO3
( Carbonic acid )
S + O2 SO2 (g)
SO2 (g) + H2O H2SO3
(sulphurous acid)
(ii) Reaction with nitric acid: Sulphur reacts with concentrated nirtric acid to form
H2SO4 and NO2.
S + 6HNO3 H2SO4 + 6NO2 (g) + 2H2O
(iii) Reaction with chlorine: Phosphorus and hydrogen reacts with chlorine to form
phosphorus trichloride and hydrogen chloride respectively.
P4 + 6Cl2 4 PCl3 (g)
H2 + Cl2 2 HCl (g)
(iv) Reaction with hydrogen:
Nitrogen reacts with hydrogen to give Ammonia.
N2 + 3H2 2 NH3
, 2. What happens when silicon is treated with (i) oxygen, (ii) chlorine, (iii) steam,
(iv) hydrochloric acid (v) sodium hydroxide.
(i) Reaction with oxygen: Silicon burns in the oxygen of air to form a white solid
compound called silicon dioxide (silica / sand).
Si + O2 SiO2
Silicon dioxide
(ii) Reaction with chlorine: On heating to a temperature of 450C, silicon combines
with chlorine to from silicon tetra chloride.
Heat
Si + 2Cl2 SiCl4
450C Silicon tetra chloride
(iii) Reaction with steam: Red hot silicon reacts with steam to form silicon dioxide
and hydrogen gas.
Heat
Si + 2H2 O SiO2 + 2H2
silicon steam Silicon hydrogen
(Red hot) dioxide
(iv) Reaction with Hydrochloric Acid: Silicon reacts with hydrochloric acid to form
silicon tetra chloride and hydrogen gas is liberated.
Si + 4HCl SiCl4 + 2H2
silicon hydrogen
tetrachloride
(iv) Reaction with sodium hydroxide: Silicon reacts with hot sodium hydroxide
solution to form sodium silicate with the evolution of hydrogen gas.
Si + 2NaOH + H2O Na2SiO3 + 2H2
sodium silicate hydrogen
