Question

Baking of roti is a physical change

• A. True
• B. False

Answer 1

The correct option is B False

Step 1 Understanding the concept: A physical change occurs when the physical qualities of a substance change.

• In most cases, a physical alteration can be reversed.
• There is no new substance generated as a result of such a reaction.
• For example, melting of ice into liquid water and freezing of the same water makes ice, there is no change in chemical composition,${\mathrm{H}}_2\mathrm{O}$.
• Chemical reactions create chemical changes, and the resulting compounds have varied properties due to the different arrangements of their atoms and molecules.
• For example; iron $Fe$ changes into iron oxide $F{e}_2{O}_3$ in the presence of water and air(oxygen).

Step 2 Explanation:

• Baking of bread is a chemical change because due to heating there is the formation of brown spots due to the reaction of reducing sugars with proteins.
• As these are the contents of flour and once formed cannot convert back to their original form, thus a new substance is formed.
• This reaction is called a mallard reaction.
• Thus, Baking roti is a physical change, which is a false statement.