Questions suggested for viva voce

QUESTIONS & ANSWERS

1. What is hardness of water 
2. What is temporary hardness and how can it be removed
3. What is permanent hardness and how can it be removed
4. What is meant by dissolved oxygen
5. What is the maximum value for dissolved oxygen in water
6. What is B.O.D (Biochemical Oxygen Demand)
7. What is C.O.D (Chemical Oxygen Demand)
8. What is alkalinity
9. Define turbidity
10. What is meant by residual chlorine
11. What is the significance of jar test
12. What is sedimentation
13. What is coagulation
14. What is flocculation
15. What are the ill-effects of hard water
16. What is BOD ?
17. What is the difference between BOD and DO(Dissolved Oxygen). If BOD is high (~300 ppm), what is the value of DO (low or high)
18. What is the difference between BOD and COD. Which is higher and why
19. What is the significance of turbidity in water treatment
20. Name the method used to determine DO
21. What is a coagulant and why is it used
22. What is residual chlorine and what is its permissible value
23. What is the permissible limit of chloride content in water
24. What is break-point chlorination
25. Why is a graph plotted to determine the optimum dosage of coagulant
26. What is the source for chlorides in water
27. What is the minimum DO content to support aquatic life
28. What is the saturation value for DO
29. Define alkalinity and its significance in water treatment
30. What is standardisation of titrant
31. Define Normality
32. What is dilution ratio and where is it used
33. What is Hypochlorous acid and what is its application
34. In the Starch-Iodide method for determination of residual chlorine, why is the flask kept in a dark place for five minutes during the standardisation of sodium thio sulphate using potassium dichromate
35. What is meant by standardisation of a reagent and why is it done
36. How are alkalinity and hardness related
37. How are hardness and alkalinity expressed
38. Expand EDTA and EB-T
39. What is 'Winkler's Test' conducted for and what is it also known as
40. What is the saturation value for DO
41. What is the permissible limit for chloride content in water
42. What are the types of alkalinities
43. What are ions contributing to alkalinity in water
44. What are the units of turbidity
45. What is meant by a 'stock solution' and what are the chemicals used to prepare stock turbidity solutions 
46. Explain how the turbidity of a solution is calculated if the meter reading is beyond the range calibrated
47. What is alum and where is it used in water treatment
48. What is the function of a coagulant
49. What happens if too little or too much of a coagulant is added to water
50. In what way are hardness and alkalinity expressed and why

ANSWERS