Engineering :: Environmental Engineering
|
|
|
|
|
41. |
Soft waters |
A. |
Have corrosive action on metals |
B. |
Dissolve lead |
C. |
Corrode iron |
D. |
All of the above |
E. |
None of the above |
|
|
Answer: Option D
Explanation:
|
42. |
The disadvantage of hard water is |
A. |
More soap consumption |
B. |
Scale formation in boilers |
C. |
Corrosion of pipes |
D. |
Loss of taste in food |
E. |
All of the above |
|
|
Answer: Option E
Explanation:
|
43. |
Identify the incorrect statement if any |
A. |
If the pH value of water is 14 the water has maximum alkalinity |
B. |
pH value of 6 represents acidic water |
C. |
Water having pH value 4 will be more acidic than water having pH value of 6 |
D. |
Maximum acidity of water is indicated by pH value of zero |
E. |
None of the above |
|
|
Answer: Option D
Explanation:
|
44. |
The pH value of sea water is usually |
A. |
1 |
B. |
Between 3 and 5 |
C. |
Between 5 and 7 |
D. |
Between 8 and 8.3 |
E. |
Between 13.7 and 14 |
|
|
Answer: Option D
Explanation:
|
45. |
The pH value of concentrated sulphuric acid could be expected between |
A. |
7 and 6 |
B. |
6 and 5 |
C. |
4 and 3 |
D. |
3 and 1 |
E. |
1 and 0 |
|
|
Answer: Option E
Explanation:
|
46. |
The permissible hardness of water for low pressure boiler is |
A. |
50 mg/litre |
B. |
150 mg/litre |
C. |
250 mg/litre |
D. |
350 kg/litre |
E. |
450 mg/litre |
|
|
Answer: Option A
Explanation:
|
47. |
The permissible hardness of water for public supplies is |
A. |
10 mg/litre |
B. |
25 mg/litre |
C. |
75 mg/litre |
D. |
115 mg/litre |
E. |
400 mg/litre |
|
|
Answer: Option D
Explanation:
|
48. |
Alum increases |
A. |
Hardness of water |
B. |
Carbonates of water |
C. |
Sulphates in water |
D. |
Acidity of water |
E. |
None of the above |
|
|
Answer: Option D
Explanation:
|
49. |
The process of kolling at the pathogenic bacteria of water-borne diseases to make it safe for hospital use, is known as |
A. |
Zeoliting |
B. |
Debacterialisation |
C. |
Sterilization |
D. |
Aeration |
E. |
Chlorination |
|
|
Answer: Option C
Explanation:
|
50. |
Prechlorination |
A. |
Improves coagulation |
B. |
Reduces odours |
C. |
Reduces organisms |
D. |
All of the above |
E. |
None of the above |
|
|
Answer: Option E
Explanation:
|
Read more:
|
|