An aqueous solution of a salt is known as brine. The salt is :
- A.Sodium chloride
- B.Potassium chloride
- C.Calcium chloride
- D.Sodium nitrate
Correct answer
Explanation
The correct answer is A, Sodium chloride. Brine is a concentrated solution of common salt, sodium chloride (NaCl), in water.
Brine occurs naturally in seawater, salt lakes and underground deposits. It is very important in industry: electrolysis of brine in the chlor-alkali process gives sodium hydroxide, chlorine gas and hydrogen gas. Brine is also used in making washing soda by the Solvay process, in preserving foods such as pickles and olives, and in melting ice on roads in cold countries. Seawater holds about 3.5 percent dissolved salts, most of it sodium chloride.
B is wrong: a potassium chloride solution is not called brine; KCl is used mainly as a fertiliser.
C is wrong: calcium chloride is a drying agent and de-icer, but its solution is not brine.
D is wrong: sodium nitrate is Chile saltpetre, not common salt.
Exam tip: brine = NaCl in water; its electrolysis (chlor-alkali process) gives NaOH, Cl2 and H2.
Practice Questions
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- B.Funaria is a fungus
- C.All Pteridophytes are Phanerogams
- D.Vascular system is not found among Bryophytes
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- A.3Cu + 8HNO3 (dilute) →
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- B.550 cal
- C.1050 cal
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- B.nitric acid
- C.sulphuric acid
- D.tartaric acid
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- A.Cell differentiation.
- B.Cell division.
- C.Cell multiplication.
- D.Cell regeneration.
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