Fill in the blanks

(a) A new substance is always formed in a …………… change.

(b) Melting of ice is a …………… change.

(c) When a candle burns, wax melts. Melting of wax is a …………… change.

(d) Chemical change occurs as a result of …………… between two substances.

(e) Burning of a fuel is a …………… change.

(f) Revolution of the earth around the sun is a …………… change.

(g) Growing of a seedling into a plant is a …………… change.

State whether the following are physical or chemical changes.

(a) glowing of a bulb

(b) burning of sugar

(c) heating of water

(d) growing of a piglet into a pig

(e) burning of wood

(f) passing electric current through a heater's rod

(g) water cycle in nature

(h) respiration in living beings

(i) shaping a piece of glass

(j) lightning

(k) dissolving sugar in water

(l) heating a mixture of iron fillings and sulphur

(m) mixing oil with water

(n) cutting wood into small pieces

(o) photosynthesis

(p) Digestion of food

(q) Melting of wax

(r) Boiling of an egg

(s) Slaking of lime

Write True or False against the following statements:

(a) Cutting of paper into pieces is a chemical change.

(b) Rusting of iron is a chemical change.

(c) Earthquake is a desirable change.

(d) Melting of ice is a physical change.

(e) Burning of sugar is a temporary change.

A substance which cannot sublime is:

1. iodine
2. camphor
3. sugar
4. dry ice