Question

It was Paheli’s birthday, her brother Simba was helping her to decorate the house for a birthday party and their parents were also busy making other arrangements. Following were the activities going on at Paheli’s home:
Simba blew balloons and put them on the wall.
Some of the balloons burst.
Paheli cut colourful strips of paper and put them on the wall with the help of tape.
She also made some flowers by origami (paper folding) to decorate the house.
Her father made dough bulls.
Mother rolled the dough balls to make Puris
Mother heated oil in a pan
Father fried the puries in hot oil.
Identify the activities at Paheli’s home as those that can be reversed and those which cannot be reversed.

Answer 1

In our day to day life we come across several kinds of change out of which some changes can be reversed or some not. On the basis of this we can say changes are further divided into two classes.
-Reversible change: That kind of changes which can be reversed or get into its original position after deforming the force are called reversible changes.
For example: Stretching of rubber band, folding of paper etc.
-Irreversible change: That kind of change which cannot be reversed into its original state is called irreversible change.
For example: Rusting of iron etc.

Complete step by step solution
Reversible change: Which can be back into its original shape called reversible changes.
Irreversible change: Which cannot be back into its original position is called irreversible change.
On the basis of the definition of irreversible and reversible change we can identify the changes that occur at Paheli’s birthday party.
Kind of activities
-Blowing of balloons: After the deflation of an air balloon can change into its original shape so it is reversible.
-Bursting of balloon: Once the balloon bursts it cannot be changed into its original shape so it is an irreversible change.
-Making colorful strips by cutting off paper: Once paper is cut into small pieces it cannot be changed into its original position. This is also an irreversible change.
-Making of flowers by folding paper: Folded paper can be changed into an original piece of paper. So this is reversible change.
-Making dough balls: Dough balls can be changed into dough again so it is reversible.
Dough balls converted into puries: Puries can be reversed to make dough bulls again.
-Heating of oil: Heating of oil is irreversible change. Because it changes into its constituent particle.
-Frying of puries: Fried puris cannot be converted into dough again so it is an irreversible change.

Note
Rather than that there are other types of change as
-Physical changes
-Chemical changes
Physical change: The kind of changes in which change only occurs in the physical state of the thing is called physical change.
For example: Magnetization of iron pieces.
Chemical change: Changes in which after applying any process like heating, oxidation etc. The change occurs in its constituent particle is called chemical change.
For example: Rusting of iron is an example of oxidation taking place at the surface of Iron due to which iron changes into iron oxide.