Salts: salts are ionic products of of acids and bases neutralisation reaction.
Acidic Salts are formed from a strong acid and a weak base.
Neutral Salts are formed from a strong acid and strong base.
Basic Salts are formed from a strong base and a weak acid.
Neutral Salt: NaCl
HCl + NaOH → NaCl + H2O
Strong Acid Strong Base Neutral Salt
Basic Salt: NaC2H3O2
HC2H3O2 + NaOH → NaC2H3O2 + H2O
Weak Acid Strong Base Basic Salt
Acidic Salt: NH4Cl
HCl + NH4OH → NH4Cl + H2O
Strong Acid Weak Base Acidic Salt
Our blood must maintain a pH around 7.35-7.45. If the pH is above 7.45 you would have a condition called alkalosis. If the pH is below 7.35, then one would suffer from acidosis.
When electricity is passed through an aqueous solution of sodium chloride (called brine), it decomposes to form sodium hydroxide. The process is called the chlor-alkali process.
This process is taken place by electrolysis of aqueous sodium chloride.
The chemical equation of this process is as folllow:
2NaCl(aq) + 2H2O(l) → 2NaOH(aq) + Cl2 (g) + H2(g)
When electricity is passed through an aqueous solution of sodium chloride (called brine), Chlorine gas is given off at the anode, and hydrogen gas at the cathode. Sodium hydroxide solution is formed near the cathode.
Products of chlor-alkali Process:
(1) Sodium Hydroxide
(2) Chlorine Gas
(3) Hydrogen Gas
Uses of Sodium Hydroxide :
(i) It is used for de-greasing Metals.
(ii) In soaps and detergents.
(iii) In Paper making.
(iv) For making of artificial fibres.
Uses of Chlorine gas:
(i) It is used In water treatment.
(ii) In swimming pool.
(iii) In manufactoring of PVC, CFCs and pesticides.
(iv) It is also used as disinfectants.
Uses of hydrogen:
(i) It is used as fuels.
(ii) It is used in Margarine.
(iii) In manufactoring of ammonia for fertilisers.
Production of Hydrochloric acid: Chlorine and Hydrogen are the main products of chlor-alkali process. These are used for production of Hydrochloric acids. Hydrochloric acid is important chemical product which is used in manufacturing of medicines, cosmetics and ammonium chloride and also used for cleaning steel.
Production of Bleaching powder: Bleaching powder is produced by the action of chlorine on dry slaked lime [Ca(OH)2]. This chlorine gas is obtained from electrolysis of aqueous sodium chloride of chlor-alkali process.
The chemical equation of this process is
Ca(OH)2 + Cl2 → CaOCl2 + H2O
Bleaching powder is used –
(i) for bleaching cotton and linen in the textile industry, for bleaching wood pulp in paper factories and for bleaching washed clothes in laundry;
(ii) as an oxidising agent in many chemical industries; and
(iii) for disinfecting drinking water to make it free of germs.
Production of Baking soda:
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 hydrogencarbonate (NaHCO3).
The chemical equation of this reaction is;
NaCl + H2O + CO2 + NH3 → NH4Cl + NaHCO3
(Ammoium Chloride) (Sodium Hydrogencarbonate)
When Sodium hydrogencarbonate is heated during cooking it gives following products.
This reaction produces carbon dioxide which is responsible for making bread or cake risen, soft and spongy.
When baking powder is heated or mixed in water, it gives carbon dioxide, water and Sodium salt of acid.
The reacton is as;
NaHCO3 + H+ → CO2 + H2O + Sodium salt of acid
Uses of sodium hydrogencarbonate (NaHCO3)
(i) For Making Baking Powder.
(ii) Sodium hydrogencarbonate is also an ingredient in antacids. Being alkaline, it neutralises excess acid in the stomach and provides relief.
(iii) It is also used in soda-acid fire extinguishers.