Q 1 – Which among the following is a physical change?
(a) Cutting a log of wood in small pieces
(b) Burning of wood
(c) Ripening of fruit
(d) Cooking of food
Ans. (a) Cutting a log of wood in small pieces
Q 2 – In which type of change a new substance is formed?
(a) In physical change
(b) In chemical change
(c) In both (a) and (b)
(d) In neither of these
Ans. (b) In chemical change
Q 3 – Which of the following is a chemical change?
(a) Bursting of a fire cracker
(b) Germination of seed
(c) Coal formation from buried trees
(d) All of these
Ans. (d) All of these
Q 4 – Which is a method to prevent rust?
(a) Crystallization
(b) Sedimentation
(c) Galvanisation
(d) None of these
Ans. (c) Galvanisation
Q 5 – How crystal of pure substances are obtained?
(a) By crystallization
(b) By chromatography
(c) By peptization
(d) By all these methods
Ans. (a) By crystallization
Q 6 – What is the formula of rust?
(a) Fe2O3
(b) Fe3O4
(c) FeO
(d) None of these
Ans. (a) Fe2O3
Q 7 – What will happen if carbon dioxide gas is passed through lime water ?
(a) Calcium carbonate is formed
(b) The lime water turns milky
(c) Both of these
(d) None of these
Ans. (c) Both of these
Q 8 – Iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
(a) It is more than 7 metres high
(b) It weighs about 6000 kg
(c) It was built more than 1600 years ago
(d) It has not rusted after such a long period
Ans. (d) It has not rusted after such a long period
Q 9 – Galvanisation is a process used to prevent the rusting of which of the following?
(a) Iron
(b) Zinc
(c) Aluminium
(d) Copper
Ans. (a) Iron
Q 10 – Paheli’s mother made a concentrated sugar syrup by dissolving sugar in hot water. On cooling, crystals of sugar got separated. This indicates a:
(a) physical change that can be reversed
(b) chemical change that can be reversed
(c) physical change that cannot be reversed
(d) chemical change that cannot be reversed
Ans. (a) physical change that can be reversed
Q 11 – Which of the following statement is incorrect for a chemical reaction?
(a) Heat may be given out but never absorbed
(b) Sound may be produced
(c) A colour change may take place
(d) A gas may be evolved
Ans. (a) Heat may be given out but never absorbed
Q 12 – Properties like size, shape, colour, state of a substance are
(a) chemical properties
(b) mental properties
(c) physical properties
(d) physico-chemical properties
Ans. (c) physical properties
Q 13 – A physical change is generally
(a) reversible
(b) irreversible
(c) considerable
(d) all of these
Ans. (a) reversible
Q 14 – During a physical change, a substance undergoes a change in its
(a) physical properties
(b) chemical properties
(c) both (a) and (b)
(d) none of these
Ans. (a) physical properties
Q 15 – Rusting of iron is a
(a) physical change
(b) chemical change
(c) both (a) and (b)
(d) all of these
Ans. (b) chemical change
Q 16 – Rusting occurs when iron is exposed to
(a) oxygen and water
(b) soil and rain
(c) breeze and sunlight
(d) salt water and clouds
Ans. (a) oxygen and water
Q 17 – When carbon dioxide is passed through lime water, the substance formed is
(a) calcium oxide
(b) calcium carbonate
(c) both (a) and (b)
(d) none of these
Ans. (b) calcium carbonate
Q 18 – A chemical change is also called a
(a) chemical reaction
(b) rusting
(c) both (a) and (b)
(d) all of these
Ans. (a) chemical reaction
Q 19 – Burning of any substance is a/an
(a) physical change
(b) chemical change
(c) irreversible change
(d) both (b) and (c)
Ans. (d) both (b) and (c)
Q 20 – The process of depositing a layer of zinc over iron is known as
(a) aluminisation
(b) galvanisation
(c) fertilisation
(d) ironing
Ans. (b) galvanization
Q 21 – Two drops of dilute sulphuric acid were added to 1 g of copper sulphate powder and then small amount of hot water was added to dissolve it (step I). On cooling, beautiful blue-coloured crystals got separated (step II). Step I and step II are
(a) physical and chemical changes respectively.
(b) chemical and physical changes respectively.
(c) both physical change
(d) both chemical change
Ans. (c) both physical change
Q 22 – Which among the following is a physical change?
(a) Burning of wood
(b) Ripening of fruit
(c) Cutting a log of wood in small pieces
(d) Cooking of food
Ans. (c) Cutting a log of wood in small pieces
Q 23 – Which of the following is a chemical change?
(a) Germination of seeds
(b) Cutting a piece of paper
(c) Bursting of fire crackers
(d) Both (a) and (c)
Ans. (d) Both (a) and (c)
Q 24 – A chemical change may bring
(a) evolution of gas
(b) change in colour
(c) change in taste
(d) all of these
Ans. (d) all of these
Q 25 – Physical changes are
(a) reversible
(b) irreversible
(c) permanent
(d) temporary.
Ans. (a) reversible
Q 26 – A change of state from one form to another is a
(a) physical change
(b) chemical change
(c) biological change
(d) state variation
Ans. (a) physical change
Q 27 – Which of the following is an example of a physical change?
(a) Mixing of baking soda and vinegar together to cause bubbles and foam.
(b) Falling of a glass cup from the counter and its shattering on the ground.
(c) Lighting a piece of paper on fire causing it to bum up and leave ashes.
(d) Baking a birthday cake for your mother.
Ans. (b) Falling of a glass cup from the counter and its shattering on the ground.
Q 28 – Which of the following is an example of a chemical change?
(a) Filling up a balloon with hot air.
(b) Taking a glass of water and freezing it by placing it in the freezer.
(c) A plant collecting sunlight and turning it into food.
(d) Your dog ripping up your homework.
Ans. (c) A plant collecting sunlight and turning it into food.
Q 29 – Which of the following changes can easily be reversed?
(a) Chemical Change
(b) Physical Change
(c) Both physical and chemical changes
(d) Neither physical nor chemical change
Ans. (b) Physical Change
Q 30 – When a new substance is formed with different properties than those of the original substance, it is called a
(a) chemical change
(b) physical change
(c) freezing
(d) boiling
Ans. (a) chemical change
Q 31 – If the chemical properties of a substance remain unchanged and its appearance or shape changes, it is called a
(a) chemical change
(b) physical change
(c) both physical and chemical changes
(d) neither physical nor chemical change
Ans. (b) physical change
Q 32 – Which of the following is an example of a physical change?
(a) Metal rusting
(b) Silver tarnishing
(c) Water boiling
(d) Paper burning
Ans. (c) Water boiling
Q 33 – Which characteristic best describes a physical change?
(a) Composition changes
(b) Composition stays the same
(c) Form stays the same
(d) Mass is lost
Ans. (b) Composition stays the same
Q 34 – Which of the following is a chemical change?
(a) Freezing of water
(b) Cutting of wood
(c) Baking of bread
(d) Bending of wire
Ans. (c) Baking of bread
Q 35 – Which of the following is not a clue that could indicate the occurrence of a chemical change?
(a) Change in colour
(b) Change in shape
(c) Change in energy
(d) Change in odour
Ans. (b) Change in shape
Q 36 – Which property stays the same during physical and chemical changes?
(a) Density
(b) Shape
(c) Mass
(d) Arrangement of particles
Ans . (c) Mass