The method to measure extent of hardness in water
is
(a) lon-exchange method (b) Lime soda method
(d) EDTA method
(c) Mean deviation
Answers
Answer:
(a) is the best answer of this question
Correct question:
The method to measure the extent of hardness in water is
(a) lon-exchange method
(b) Lime soda method
(c) Mean deviation
(d) EDTA method
The method to measure the extent of hardness in water is (d) EDTA method.
EDTA method:
The EDTA complexometric titration method is widely used in chemical analysis to determine the hardness of the water that is a buffer solution of pH 10.
Explanation of incorrect options:
(a) lon-exchange method:
The exchange of calcium and magnesium ions in hard water with different anions or cations in exchangers is the ion exchange process. So it cannot be used to measure the extent of hardness in water.
(b) Lime soda method:
The lime soda method is a technique for softening hard water. So it cannot be used to measure the extent of hardness in water.
(c) Mean deviation:
The mean deviation is the average of the absolute deviations from a suitable average of the observations or values. So it cannot be used to measure the extent of hardness in water.
Hence, The EDTA method is used to determine the amount of hardness in water.