Describe the changes on the basis of different criteria in
(a) Frying a puri
(b) Light coming out of an electric bulb
(c) Rolling out dough into chapattis
(d) A tree falling in a storm
(e) Sharpening a knife’s blade.
Describe the changes on the basis of different criteria in
(a) Frying a puri
(b) Light coming out of an electric bulb
(c) Rolling out dough into chapattis
(d) A tree falling in a storm
(e) Sharpening a knife’s blade.
(a)Frying a puri is a chemical change since it can not be reversed and involves changes in its chemical properties.
(b)When electricity is passed through the bulb (tungsten ) the electrons in the atoms get excited and release the energy as light in terms of photons. So no chemical reaction is taking place. It is physical change
(c)Rolling of chapati is an example of physical change there is no new substance formed in this.
(d) A tree falling in storm is an example of an irreversible change .
Irreversible change : Changes that cannot be reversed are called irreversible changes.
(e ) Sharpening a knife’s blade is an example of physical change because there is no new substance formed during this change.
(a)Frying a puri is a chemical change since it can not be reversed and involves changes in its chemical properties.
(b)When electricity is passed through the bulb (tungsten ) the electrons in the atoms get excited and release the energy as light in terms of photons. So no chemical reaction is taking place. It is physical change
(c)Rolling of chapati is an example of physical change there is no new substance formed in this.
(d) A tree falling in storm is an example of an irreversible change .
Irreversible change : Changes that cannot be reversed are called irreversible changes.
(e ) Sharpening a knife’s blade is an example of physical change because there is no new substance formed during this change.
