Answer / guest

Physical change:-

(1) Only the physical properties of the substance changes
and the composition remains the same

(2) No new substances obtained

(3) The change is temporary can be reversed by ordinary
physical means

Chemical Changes:

(1) Chemical composition of the substance is changed

(2) New substance with entirely different properties obtained

(3) The change is permanent and cannot be reversed by
ordinary physical means

(4) The formula which gives the actual present in the
molecule of substance

Answer / srishti

physical changes are changes in the physical properties of
substances. No new substance is formed in this change.
These changes may be reversible.
In chemical changes new substances are produced

Answer / aman

the basic difference between physical and chemical change are:

physical

1.if these substances change their state they will return to
its normal state.for eg. if water changes into water vapour
or solid ice it well evaporate or condense and will change
into water.

2.their physical appearance and composition are changed.

3.it is temporary contrast to chemical.

4.no new substances are formed.



chemical

all the points when are contrasted (opposite of the points
above). for eg. a paper when burns change into ash so new
substance is formed this is example for new substance and
chemical change.

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