| 1 |
The residence time of NO is |
- A. Few hours
- B. 1 day
- C. 3 days
- D. 4 days
|
| 2 |
The avoid the formation of toxic compounds with chlorine which substance is used for disinfecting water |
- A. KMnO<sub>4</sub>
- B. O<sub>3</sub>
- C. Alums
- D. Chloramines
|
| 3 |
The avoid teh formation of toxic compounds with chlorine which substance is used for disinfecting water. |
- A. KMnO4
- B. O3
- C. Alum
- D. Chloramines
|
| 4 |
Ecosystem is smaller unit of |
- A. Lithosphere
- B. Hydroshpere
- C. Amosphere
- D. Biosphere
|
| 5 |
On earth polar ice caps and glacier contains H2O |
|
| 6 |
Water will be considered polluted if it has dissolved oxygen. |
- A. 3ppm
- B. 4ppm
- C. 5ppm
- D. 6 ppm
|
| 7 |
A single chloride free radical can destroy how many ozone molecules |
- A. 100
- B. 100,000
- C. 100,00
- D. unlimited
|
| 8 |
In purification of potable water the coagulant used is |
- A. Nickel sulphate
- B. Copper sulphate
- C. Barium sulphate
- D. Alum
|
| 9 |
In water the concentration of dissolved O<sub>2</sub>should be |
- A. 1-3 ppm
- B. 2-4 ppm
- C. 4-8 ppm
- D. 8-12 ppm
|
| 10 |
The pH range of the acid rain is. |
- A. 7-6.5
- B. 6.5-6
- C. 6-6.5
- D. Less than 5
|
