Question

Which of the following is a chemical reaction? A.breaking a glass pane B.freezing water B.digestion of food C.cutting down a tree D.evaporation of rubbing alcohol

Answer 1

The correct answer is option B, that is, digestion of food.

Digestion of food in the body is a decomposition reaction, it is a kind of chemical reaction in which single compound dissociates into two or more basic components. In the process of digestion, proteins, carbohydrates, and fats dissociate to basic constituents, which provide energy to function.  

Digestion of food is regarded as chemical change as different chemical reactions occur at the time of food digestion.  

Answer 2

The answers A. C. D. are all physical reactions 

The answer is B. Digestion of food 

When food is digested it is chemically broken down 

Hope this help!