1. A sample of domestic sewage is digested with silver sulphate, sulphuric acid, potassium dichromate and mercuric sulphate in chemical oxygen demand (COD) test. The digested sample is then titrated with standard ferrous ammonium sulphate (FAS) to determine the un-reacted amount of

1. 1. mercuric sulphate

   
   
   

   2. potassium dichromate

   
   
   

   3. silver sulphate

   
   
   

   4. sulphuric acid

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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2. Group I lists estimation methods of some of the water and waste water quality parameters. Group II lists the indicators used in the estimation methods. Match the estimation method (Group I) with the corresponding indicator (Group II).
   

1. 1. P-3, Q-2, R-1, S-4

   
   
   

   2. P-4, Q-2, R-1, S-3

   
   
   

   3. P-4, Q-1, R-2, S-3

   
   
   

   4. P-4, Q-2, R-3, S-1

   
   
   

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   NA

   Correct Option: A

   NA

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3. Match group I (Terminology) with group II (Definition/Brief Description) for waste water treatment systems.
   

1. 1. P-4, Q-3, R-1, S-2

   
   
   

   2. P-4, Q-3, R-2, S-1

   
   
   

   3. P-3, Q-4, R-2, S-1

   
   
   

   4. P-1, Q-2, R-3, S-4

   
   
   

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   NA

   Correct Option: A

   NA

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4. Column I	Column II
   P. Grit chamber	1. Zone settling
   Q. Secondary settling tank	2. Stoke’s law
   R. Activated sludge process	3. Aerobic
   S. Trickling filter	4. Contact stabilisation

   
   The correct match of Column I with Column II is

1. 1. P-1, Q-2, R-3, S-4

   
   
   

   2. P-2, Q-1, R-3, S-4

   
   
   

   3. P-1, Q-2, R-4, S-3

   
   
   

   4. P-2, Q-1, R-4, S-3

   
   
   

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   NA

   Correct Option: B

   NA

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5. Match the following
   

   Group I	Group 2
   P. Thickening of sludge	1. Decrease in volume of sludge by chemical oxidation
   Q. Stabilization of sludge	2. Separation of water by heat or chemical treatment
   R. Conditioning of sludge	3. Digestion of sludge
   S. Reduction of sludge	4. Separation of water by flotation or gravity

1. 1. P- 4, Q-3, R-1, S-2

   
   
   

   2. P- 3, Q-2, R-4, S-1

   
   
   

   3. P- 4, Q-3, R-2, S-1

   
   
   

   4. P- 2, Q-1, R-3, S-4

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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