Anaerobic bacteria digest animal waste and produce biogas (Change – A). The biogas is then burnt as fuel (Change – B). The following statements pertain to these changes. Choose the correct one. (i) Process – A is a chemical change. (ii) Process – B is a chemical change (iii) Both processes A and B are chemical changes. (iv) None of these processes is a chemical change.
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Solution:
The answer is (iii) Both processes A and B are chemical changes.
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