Our body works within the pH range of 7.0 to 7.8. Living organisms can survive only in a narrow range of pH change. When pH of rain water is less than 5.6, it is called acid rain. When acid rain flows into the river, it lowers the pH of the river water. The survival of aquatic life in such rivers becomes difficult.
1. Survival of animals in _____ water is difficult.
(i) Acidic
(ii) Alkaline
(iii) Neutral
(iv) None of these.
2. Typical acid rain has a pH value of
(i) 2
(ii) 7
(iii) 11
(iv) 4
3. pH of our body is slightly
(i) Acidic
(ii) Alkaline
(iii) Neutral
(iv) None of these
4. Optimal pH for many aquatic species is between
(i) 7 to 9
(ii) 11 to 14
(iii) 4 to 6
(iv) 14.
5. True or false. Low pH levels cause fish kill by stressing animal systems and causing physical damage, which in turn makes them more vulnerable to disease.
(i) TRUE
(ii) FALSE
