The document discusses how common salt (sodium chloride) is used as a raw material to produce various chemicals. It describes the production of sodium hydroxide, bleaching powder, baking soda and washing soda from sodium chloride. Sodium hydroxide is produced through the electrolysis of sodium chloride solution. Bleaching powder is made by reacting chlorine gas with slaked lime. Baking soda is produced from sodium chloride, water, carbon dioxide and ammonia. Washing soda is obtained by crystallizing sodium carbonate. These chemicals find applications in industries and domestic uses.
3. COMMON SALT A RAW
MATERIAL FOR CHEMICALS.
Common Salts (NaCl) are Ironic compounds that result from
the Neutralization reaction of an Acid and a Base.
Common Salt is an important raw material for Various materials
in our daily life.
A few of the materials are
1.Sodium Hydroxide. 2. Bleaching powder(Calcium Oxy chloride)
3. Baking Soda(Sodium bicarbonate). 4. Washing Soda(Sodium
carbonate)
4. 1. SODIUM
HYDROXIDE(NaOH)
When electricity passes through an aqueous solution of
Sodium Chloride (Also known as Brine)it decomposes to from
NaOH, This process is called Chlor-Alkali
It is known as chlor-Alkali because the products form Chlor
for Chlorine and Alkali for NaOH
Chlorine gas is given off at the Anode, and Hydrogen gas at
the Cathode. These gases Are very useful to us.
6. PROPERTIES OF NaOH.
It Has an Acidity of 13.
Reacts with Carbon Dioxide to form Sodium Carbonate.
Also reacts with other Acids to form pure water and salts.
Chemical Equation:
2NaCl(aq) + 2H2O Gives 2NaOH(aq) + Cl2(g) + H2(g).
7. Bleaching powder(CaOCl2).
We know that chlorine is produced during electrolysis of
aqueous sodium chloride(brine).This Chlorine gas is used for
manufacture of bleaching power(CaOCl2).
Bleaching powder is produced by the action of chlorine on
dry Slaked Lime(Ca(OH)2).
8. Uses of CaOCl2
It is used for bleaching cotton and linen in the textile
industry, for bleaching wood pulp in paper factories and
for bleaching washed clothes in laundry
as an oxidizing agent in many chemical industries; and
for disinfecting drinking water to make it free of
germs.
10. Baking soda(Sodium Bi-
Carbonate)
The soda commonly used in the kitchen for making tasty crispy
pakoras is baking soda. Sometimes it is added for faster cooking. The
chemical name of the compound is sodium hydrogen carbonate
(NaHCO3). It is produced using sodium chloride as one of the raw
materials.
NaCl + H2O + CO2 + NH3 Gives NH4Cl + NaHCO3
It is a mild non-corrosive base.
2NaHCO3 Gives Na2CO3 +H2O+CO2
11. Uses of sodium hydrogen carbonate
(NaHCo3)
For making baking powder, which is a mixture of baking
soda(sodium hydrogen carbonate) and a mild edible acid
such as tartaric acid. When baking powder is heated or
mixed in water, the following reaction takes place –
NaHCO3 + H+ → CO2 + H2O + Sodium salt of acid
Carbon dioxide produced during the reaction causes
bread or cake to rise making them soft and spongy.
12. Uses of sodium hydrogen
carbonate (NaHCo3)
Sodium hydrogen carbonate is also an ingredient in antacids.
Being alkaline, it neutralizes excess acid in the stomach and
provides relief.
It is also used in soda-acid fire extinguishers.
14. WASHING SODA
Another chemical that can be obtained from sodium chloride
is Na2CO3.10H2O (washing soda). You have seen above that
sodium carbonate can be obtained by heating baking soda;
recrystallization of sodium carbonate gives washing soda. It is
also a basic salt.
Na2CO3 +H2O Gives Na2CO3.H2O
15. USES OF WASHING SODA
Sodium carbonate (washing soda) is used in glass, soap and
paper industries.
It is used in the manufacture of sodium compounds such as
borax.
Sodium carbonate can be used as a cleaning agent for
domestic purposes.
It is used for removing permanent hardness of water.