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Question
When the concentrated aqueous solution of substance X is electrolysed, then NaOH, Cl2 and H2 are produced. Name the substance X. What is the special name of this process?
Solution
Substance X, which gives sodium hydroxide, Cl2 and H2 upon electrolysis, is NaCl. The electrolysis of sodium chloride solution is called the chlor-alkali process because of the products formed, 'chlor' for chlorine and 'alkali' for sodium hydroxide (NaOH).
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RELATED QUESTIONS
Name the major salt present in sea-water.
Complete and balance the following chemical equations:
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|
(1) |
Calcium Sulphate |
(2) |
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|
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|
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The Salt Story
From: The New Indian Express 9 March 2021
The salt pans in Marakkanam, a port town about 120 km from Chennai are the third largest producer of salt in Tamil Nadu. Separation of salt from water is a laborious process and the salt obtained is used as raw materials for manufacture of various sodium compounds.
One such compound is Sodium hydrogen carbonate, used in baking, as an antacid and in soda acid fire extinguishers.
The table shows the mass of various compounds obtained when 1litre of sea water is evaporated.
| COMPOUND | FORMULA | MASS OF SOLID PRESENT /g |
| Sodium Chloride | NaCl | 28.0 |
| Magnesium Chloride | MgCl2 | 8.0 |
| Magnesium Sulphate | MgSO4 | 6.0 |
| Calcium Sulphate | CaSO4 | 2.0 |
| Calcium Carbonate | CaCO3 | 1.0 |
| TOTAL AMOUNT OF SALT OBTAINED | 45.0 | |
What is the pH of the acid which is used in the formation of common salt?
Salt is ______ in nature.
Salt which is formed by the partial replacement of hydrogen ions of an acid by a metal is called ______.
You are provided with the list of chemicals mentioned below in the box:
| Sodium hydroxide solution, copper carbonate, zinc, hydrochloric acid, copper, dilute sulphuric acid, chlorine, iron |
Using suitable chemicals from the list given, write a balanced chemical equation for the preparation of the salt mentioned below:
Sodium zincate
