Question

Anaerobic bacteria digest animal waste and produce biogas (Changed A). The biogas is then burnt as fuel (Change B). The following statements are related to these changes. Choose the correct one.
A) A is a chemical change whereas B is a physical change. B) 5 is a chemical change whereas A is a physical change. C) Both A and 5 are physical changes. D) Both A and B are chemical changes.

Answer 1

the ans. will be D) Both A and B are chemical changes.

hope helped.

Answer 2

d: both a and b are chemical changes