Question

Animal dung is digested to produce biogas (process A). The biogas is used in the stove as a fuel (process B), which of the following is correct?
A.Process A is a chemical change.
B.Process B is a chemical change.
C. Both A and B are chemical changes.
D.Neither A or B is a chemical change.

Answer 1

Hint: Biogas produced from the organic waste which bio grades by means of bacteria in an anaerobic environment. It forms by the decomposition in absence of oxygen, which releases biogas. It is a type of biofuel that is produced from organic waste. It is the composition of methane, carbon dioxide, hydrogen, nitrogen and hydrogen sulphide.

Complete step by step answer:
 Plants and animals consist of waste material of carbohydrates, lipids, proteins and metabolites which are mostly insoluble in water. These biodegradable materials undergo decomposition.
These materials incubated and combustible gas which is known as methane. It produces the action of bacteria.
The degradation process also takes place and takes a long time. The anaerobic process is also partly dependent on temperature and faster is digestion and biogas production.
Here, cooking with biogas used as a manure in the field.
As well as animal dung is digested to produce biogas because it is an organic material and used in a stove as a fuel.

Hence, the correct answer is option (C).

Note:
To charge the produce for the operating digester, animal dung mixed with water. Then the digester starts with operation and produces biogas daily for cooking or other uses like gas lamps. All anaerobic digestion systems have the same principle whether feedstock is food waste, animal manures or wastewater sludge. The process is the same to form a biogas plant.