(i) Change in colour: Reaction between lead nitrate solution and potassium iodide solution.
Pb(NO3)2(aq)+2KI → PbI2(s)+2KNO3(aq)
In this reaction, colour changes from colourless to yellow.
(ii)Change in temperature: Action of dilute sulphuric acid on zinc.
Zn(s)...
Light green is the Colour of crystalline FeSO4.7H2O. Light green changes to reddish brown or brown upon heating.
(i) FeSO4.7H2O+heat → FeSO4+7H2O
(ii) 2FeSO4+heat → Fe2O3+SO2+SO3
On mixing the clear solution of two ionic compounds, as a substance which is insoluble in water, is formed. This insoluble substance is known as a formed is called precipitation...
CuSO4 + Fe → FeSO4 + Cu
CuSO4 -(Blue)
FeSO4 - (Green)
Iron is more reactive than copper. Hence it displaces copper from copper sulphate and due to formation of FeSO4, the colour changes from blue to green.
(i) CuSO4.SH2O
CuSO4.5H2O Heat →CuSO4+5H2O
CuSO4.5H2O-(Blue)
CuSO4+5H2O-(White)
(ii) Explanation: On heating, crystal loses water of crystallisation and regain it on cooling
Chemical formula -CaOCl2
Chemical equation -
Ca(OH)2+Cl2 →CaOCl2+H2O
Uses:
(i) For bleaching cotton and linen in the textile industry
(ii) As an oxidising agent in a chemical industry.
(iii) For disinfecting water.
Copper sulphate crystals (CuSO4.5H2O)
5 molecules of water are present in one formula unit of copper sulphate. When heated, its loses its water and salt turns white.
