5. Give taler examples of Physical and chemical changes each.
Explain whether each change is tast ar slow, natural
or man-made , Periodic ar non- Periodic, reversible or irreversible
Answers
Answer:
Examples of physical changes:
stretching of a rubberband, folding of a paper... The speed of that change depends on that person who is making this certain changes......
they are reversible..
Examples of chemical changes : burning of a paper, burning a wood...
These changes can sometimes either fast and even slow too..
these changes are irreversible..
Physical change
*The chemical composition of a substance does not change
*The chemical composition of a substance does not change *Easily reversible.
*The chemical composition of a substance does not change *Easily reversible.*No new substance is formed.
*The chemical composition of a substance does not change *Easily reversible.*No new substance is formed.*Melting of ice is an example of physical change.
chemical change
*The chemical composition of a substance does not remain same
*The chemical composition of a substance does not remain same *Not easily reversible
*The chemical composition of a substance does not remain same *Not easily reversible *New substances are always formed.
Periodic changes
*Events that repeat themselves after a fixed period of time and whose ocurence can be predicted are called periodic changes.
*Events that repeat themselves after a fixed period of time and whose ocurence can be predicted are called periodic changes.* Example- rotation of earth, revolution of earth, day and night, seasons etc.
Non periodic changes
*The events that do not repeat themselves after regular interval of time are called non periodic changes.
*The events that do not repeat themselves after regular interval of time are called non periodic changes.*Example- natural disasters like earthquake, cyclones etc.