Mention a change which is always
(a) desirable
(b) undesirable
(c) periodic
46 Likes
(a) Photosynthesis
(b) Rusting of iron
(c) Change of day and night
Answered By
27 Likes
Define:
(a) a physical change
(b) a chemical change
(c) Give two examples for each of the above two changes.
What are reversible and irreversible changes? Give one example for each.
Is burning a physical change or a chemical change? Why?
A burning candle shows both physical and chemical changes. Explain.