Question

differentiate between physical and chemical change class 9 chapter 2

Answer 1

Answer:

Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula.

Explanation -

1)No new substance is formed in the physical change. A new substance is formed in a chemical change. 2)Physical change is temporary change. A chemical change is a permanent change. ... A lot of heat or light energy is absorbed or given out in a chemical change.

Answer 2

Answer:

Physical Change -:

• When a substance undergoes a physical change, its composition remains the same despite its molecules being rearranged.
• Physical change is a temporary change.
• A Physical change affects only physical properties i.e. shape, size, etc.

Chemical Change-:

• When a substance undergoes a chemical change, its molecular composition is changed entirely. Thus, chemical changes involve the formation of new substances.
• A chemical change is a permanent change.
• Chemical change both physical and chemical properties of the substance including its composition.