properties and uses:
a.bleaching powder
b.baking soda
c.washing soda
Answers
bleaching powder
It is produced by the action of Chlorine on dry slaked lime. It is represented as CaOCl2, though the actual composition is quite complex.
Ca(OH)2 + Cl2 → CaOCl2 + H2O
On standing for a longer time, it undergoes auto oxidation due to which bleaching action decreases.
Uses of Bleaching Powder:-
(i) It is used for bleaching cotton and linen textile industry, for bleaching wood pulp in paper industry and for washed clothes in laundry.
(ii) It is also used as a disinfectant for water to make it germ free.
(iii) It is used as an oxidizing agent in many chemical industries.
Sodium bicarbonate or Baking soda
Formula: NaHCO3
Properties:
Sodium hydrogen carbonate is a white crystalline solid having a density of about 2.2 g/mL. It has alkaline taste and is sparingly soluble in water. The solubility of sodium hydrogen carbonate increases with the rise of temperature.
Uses of sodium bicarbonate or Baking soda
1. As a component of baking powder.
2. In fire extinguishers.
3. In medicines as a mild antiseptic for skin diseases and to neutralize the acidity of the stomach.
4. As a reagent in laboratory.
Washing Soda
Washing soda is sodium carbonate containing 10 molecules of water of crystallisation.It is called as sodium carbonate decahydrate.
The formula of washing soda is
Na2CO3.10H2O
Sodium carbonate which does not contain any water of crystallisation is called anhydrous sodium carbonate or soda ash.The formula is Na2CO3
It is prepared by Solvay’s process.
it's properties are
1)It is a white transparent crystalline solid.
2)It is soluble in water.
3)The solution of washing soda in water is alkaline which turns red litmus to blue.
4)It has cleansing properties.
it's uses are
1)It is used to remove permanent hardness of water.
2)It is used in the manufacture of glass,soap,paper.
3)It is used for washing clothes.
4)It is used in the manufacture of borax.
A.Bleaching powder:
Chlorine gas obtained in the electrolysis is used for the manufacture of bleaching powder. Chlorine gas on reacting with dry slaked lime [Ca(OH)2] produces bleaching powder (CaOCl2).
Uses of bleaching powder:
Bleaching powder is used for disinfecting water to make it germ-free. It is used in the textile industry to produce cotton and linen materials. It is also used as an oxidizing agent in many chemical industries.
C. Uses of Washing Soda:
Washing soda is used for removing burnt-on grease from kitchen utensils.
It is prominently used in soap, glass and paper industries.
It also helps in the removal of permanent hardness of the water.
It acts as a raw material in the manufacturing of various sodium compounds, for example, borax.
Preparation of Washing Soda
Washing soda is synthesized through Solvay’s process. Solvay’s process involves the reaction of sodium chloride, ammonia and carbon dioxide in water. Carbon dioxide involved is produced through calcium carbonate and the calcium oxide left is used in recovering ammonia from ammonium chloride.
At first, sodium bicarbonate is obtained which is then converted to sodium carbonate on heating. Finally, washing soda is produced by recrystallization of sodium carbonate.
C.Uses of Baking Soda
It is used in making soft and fluffy bread and cakes due to the production of carbon dioxide when it is heated or mixed in water.
NaHCO3 + H+ → CO2 + H2O + sodium salt of acid
It is used for making soda-acid fire extinguisher.
It is used as an ingredient in the manufacturing of antacids.
Baking soda is synthesized through Solvay’s process. Solvay’s process involves the reaction of sodium chloride, ammonia and carbon dioxide in water. The carbon dioxide involved is produced through calcium carbonate and the calcium oxide left is used in recovering ammonia from ammonium chloride. Finally, sodium bicarbonate is produced as one of the end products.