Chemistry
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
Answer
(a) glowing of a bulb — Physical change
(b) burning of sugar — Chemical change
(c) heating of water — Physical change
(d) growing of a piglet into a pig — Chemical change
(e) burning of wood — Chemical change
(f) passing electric current through a heater's rod — Physical change
(g) water cycle in nature — Physical change
(h) respiration in living beings — Chemical change
(i) shaping a piece of glass — Physical change
(j) lightning — Chemical change
(k) dissolving sugar in water — Physical change
(l) heating a mixture of iron fillings and sulphur — Chemical change
(m) mixing oil with water — Physical change
(n) cutting wood into small pieces — Physical change
(o) photosynthesis — Chemical change
(p) Digestion of food — Chemical change
(q) Melting of wax — Physical change
(r) Boiling of an egg — Chemical change
(s) Slaking of lime — Chemical change
Related Questions
Name a chemical change which takes place in presence of:
(a) Heat
(b) Light
(c) Electricity
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.
Match the following:
Column A Column B (a) Evaporation of water (i) Non-periodic change (b) Milk turning sour (ii) Periodic change (c) Earthquake (iii) Chemical change (d) Change of seasons (iv) Physical change (e) Glowing of bulb (v) Reversible change 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.