[ps2id id=’background’ target=”/]
World consists of 70% water which coincides with the body’s water content and the pollution of water causes major health problems. Although it is not possible to completely eradicate water born diseases which explains for the improper sterilization of water.
The purity testing is done to keep the drinking water clean and the water of reservoirs or ponds where is stagnant, the water which are transported has to undergo this test for purity.1
Aim: Aim of the experiment is to perform various tests to ensure the purity of water.
[ps2id id=’requirements’ target=”/]
Chemicals: Methyl red,
Dilute ammonium chloride,
Silver nitrate solution,
Barium chloride solution,
Disodium ethylene diamine tartaric acid,
Potassium mercuric iodide.
Test tube holder,
[ps2id id=’procedure’ target=”/]
pH of water is 4.0 .
Test for acidity and alkalinity
10ml of freshly prepared purified water was taken ina test tube and to this 0.05ml of methyl red solution was added. The resulting solution doesn’t turn blue. In an another test tube, 10ml of purified water was taken and to this 0.1ml of bromothymol blue solution was added and the resulting solution doesn’t turn blue.
Test for Ammonia
About 5ml of purified water was taken in a test tube and to it 0.5ml of dragendorff reagent was added. Then it was allowed to stand for 5min. In an another test tube, 3.75ml of purified water was taken and to this 1.25ml of ammonium chloride solution was added followed by 0.5ml of alkaline potassium mercuric chloride solution.
Test for calcium and magnesium
About 10ml of purified water was taken and to this 0.2ml of ammonia solution was added. To this moderant black –II was added followed by 0.5ml of DSDT acid. A purple colour was developed.
Test for chloride
About 10ml of purified water was taken in a test tube and to this 1ml of 2N nitric acid was added followed by 2ml of 0.1M silver nitrate solution. The appearance of the solution was not changed for 15 minute.
Test for sulphate
About 10ml of purified water was taken in a test tube and to this 0.1ml of 2M HCl was added followed by addition of 0.1ml of barium chloride solution. The appearance of the solution doesn’t change for 1 hour.
Test for oxidizable substances
About 10ml of purified water was taken in a test tube and to this 1ml of sulphuric acid solution was added followed by addition of 0.1ml of 0.02M KMnO4 solution. It was boiled for 5minutes. The solution remains faint pink colour.
[ps2id id=’conclusion’ target=”/]
By performing the above tests, it can be concluded that the water has passed the purity test.
[ps2id id=’references’ target=”/][ps2id id=’1′ target=”/]
Inorganic medicinal and pharmaceutical chemistry., Block, Roche, Soine, Wilson.
Indian Pharmacopoeia, 1996, 2016.
Chatwal GR. Pharmaeutical Chemistry Inorganic.