Question

physical change and chemical chang with example​

Answer 1

Answer:

the change which is temperory and can be reverse again is called physical change.

ex. transformation of ice into water.

the change which is permanent and cannot be reverse again.

ex. cooking of food

Answer 2

Answer :-

• define physical change ?

The change in which no new substance is formed and can reverse by reversing is called a physical change.

• define chemical change ?

A change in which new substance

is formed and can't be reversed by reversing is called chemical change.

• Examples of physical change ?

⠀⠀(i) glowing of bulb

⠀⠀(2) Melting of butter

⠀⠀(3) Melting of wax

⠀⠀(4) Heating of iron

⠀⠀(5) Formation of cloud.

• Examples of chemical change ?

⠀⠀⠀(i) Burning of fuel

⠀⠀⠀(2) Change of milk into cheese

⠀⠀⠀(3) Change of milk into curd

⠀⠀⠀(4) Cooking of food

⠀⠀⠀(5) Burning of incense stick.

_____________

⠀⠀⠀⠀Additional :-

Desirable change :-

The change in which we want to occur, is called desirable change.

Undesirable change :-

The change which we don't want to occur is called undesirable change.

Examples of desirable change :-

• Burning of firewood in a chulha
• Dormation of curd
• Change of cow dung into biogas

Examples of undesirable change :-

• Forest fire and burning of wood
• Spoilage of milk and changing into curd
• Breaking of glass tumbler