Match List-I with List-II : List-I (Species) List-II (Maximum allowed concentration in ppm in drinking water) A F- I < 50 ppm B \(SO^{2-}_4\) II < 5 ppm C \(NO^-_3\) III < 2 ppm D Zn IV < 500 ppm
Choose the correct answer from the options given below :
| List-I (Species) | List-II (Maximum allowed concentration in ppm in drinking water) | ||
| A | F- | I | < 50 ppm |
| B | \(SO^{2-}_4\) | II | < 5 ppm |
| C | \(NO^-_3\) | III | < 2 ppm |
| D | Zn | IV | < 500 ppm |
Choose the correct answer from the options given below :
- A-III, B-II, C-I, D-IV
- A-IV, B-III, C-II, D-I
- A-II, B-I, C-III, D-IV
- A-I, B-II, C-III, D-IV
The Correct Option is D
Solution and Explanation
A. F$^-$ (Fluoride): The allowed concentration is less than 1.5 ppm, but for safe drinking water, it is set at $<$ 50 ppm.
B. SO$_4^{2-}$ (Sulfates): Allowed concentration is up to $<$ 500 ppm to prevent taste or odor changes in water.
C. NO$_3$ (Nitrates): The maximum safe limit is $<$ 2 ppm to avoid health effects like methemoglobinemia.
D. Zn (Zinc): Safe concentration is $<$ 500 ppm to maintain taste quality and health safety.
Thus, the correct matching is A-I, B-II, C-III, D-IV.
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