Classify the following changes as physical and chemical changes
A rough piece of wood is sanded and polished resulting in change in texture, Rusting of a iron nail, Painting the grill, Bending a paper clip, Pounding silver into thin plate, Rolling the chappathi dough into thin wire, Occurrence of day and night, eruption of volcano, burning of matchstick, dosa from the batter, blinking of eyelids, occurrence of a thunderstorm, rotation of the earth, formation of eclipses.

Physical changes	Chemical changes

Distinguish physical and chemical changes.

How can a change occur in a substance?

Can you suggest a method to collect water from sea water?

What is the difference between dissolution of sugar and burning of sugar?

Explain the following statement: Digestion is a chemical change.

How the iron blade is fixed into a wooden handle in tools used to dig the soil?

Peeled and unpeeled banana does not look the same. Does that mean peeling banana is a chemical change?

A very hot glass on putting in cold water cracks. What does this change indicate?

Boiling of water is a physical change; but boiling of egg is a chemical change. Why?