Answer: (iii) Both processes A and B are chemical changes
Physical change – A substance is said to undergo a physical change when only the physical properties such as the shape, size, colour, state or appearance of the substance change. Its chemical composition remains intact.
Chemical change – A substance is said to undergo a chemical change when the chemical properties of a substance alter. As a result, there is either formation or breaking of atomic bonds at the molecular level.
- The decomposition of animal waste produces biogas.
- A chemical change is illustrated by the decomposition process, which involves changes in the composition of the components involved. As a result, Process A is an instance of chemical transformation.
- When biogas is burnt, it undergoes chemical transformation, resulting in the formation of new products.
- In response to the question, it’s important to note that both processes A and B involve chemical changes.