Paheli observed that most of the fish in the pond of her village were gradually dying. She also observed that the waste of a factory in their village was flowing into the pond, which probably caused the fish to die. (a) Explain why the fish were dying. (b) If the factory waste is acidic in nature, how can it be neutralised?
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Soln:
a) As Factory waste is disposed of in the river, it can kill the fish as factory waste may contain acids, bases and other toxic compounds.
b) If the factory waste is acidic in nature, it can be neutralised by adding basic substances.
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