Class 7 Science MCQ Physical and Chemical Changes

Question : A change in which a substance undergoes changes in its physical properties is called __________________________.

(a) Chemical change
(b) physical change
(c) No change
(d) Biological change

Question : When carbon dioxide is passed through lime water , then lime water becomes __________________________.

(a) milky
(b) shiney
(c) silvery
(d) Golden yellow

Question : Brown colour of the apple after cutting is __________________________.

(a) physical change
(b) chemical change
(c) no change
(d) biological change

Question : Ozone layer protects us from harmful __________________________.

(a) Ultraviolet radiation
(b) Infrared Radiation
(c) Visible Radiation
(d) Heat radiation

Question : The process of depositing a layer of one metal over another metal surface to protect it from rusting is called __________________________.

(a) Galvanisation
(b) Crystallisation
(c) amalgamating
(d) Neutralisation

Question : For protecting iron pipes from corrosion, they are coated with __________________________.

(a) Zinc
(b) Copper
(c) Aluminium
(d) Silver

Question : Metal that is made by mixing iron with carbon, nickel and manganese is called __________________________.

(a) Stainless steel
(b) German silver
(c) Nichrome
(d) Eureka

Question : The process of obtaining Salt by the evaporation of sea water is called __________________________.

(a) Crystallisation
(b) Neutralisation
(c) Galvanisation
(d) Amalgamation

Question : Blue colour of the copper sulphate solution changes to Green colour when an iron nail is dropped into it due to the formation of __________________________.

(a) Iron sulphate
(b) copper chloride
(c) Copper iron sulphate
(d) Iron chloride

Question : When Magnesium ribbon is burnt in oxygen, the product obtained is __________________________.

(a) Magnesium chloride
(b)Magnesium sulphate
(c) Magnesium oxide
(d) Iron chloride

Question : Magnesium hydroxide, obtained when Magnesium oxide is dissolved in water, is __________________________.

(a) a Base
(b) An acid
(c) an indicator
(d) a dissolving agent

Question : When Magnesium ribbon is burnt in candle flame it burns with __________________________.

(a) brilliant red light
(b) Brilliant yellow light
(c) Brilliant white light
(d) Brilliant Green light

Question : Which of the following changes is accompanied by sound?

(a) Photosynthesis
(b) Spoilage of food
(c) Explosion of fire works
(d) None of these

Question : 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

Question : Which characteristic best describes a physical change?

(a) Composition changes
(b) Composition stays the same
(c) Form stays the same
(d) Mass is lost

Question : Burning of any substance is a/an

(a) physical change
(b) chemical change
(c) irreversible change
(d) both (b) and (c)

Question : The process of forming substances in their pure state from their solution is known as:

(a) galvanisation
(b) neutralisation
(c) crystallisation
(d) all of these

Question : The reason for a physical change to be named as such is that the:

(a) change occurs only in physical properties
(b) transfer of energy takes place
(c) is a reversible change
(d) All of the above

Question : When wax vapours burns then smoke and carbon dioxide are formed which are new substances, is a:

(a) physical change
(b) chemical change
(c) both (a) and (b)
(d) none of these

Question : Properties like size, shape, colour, state of a substance are

(a) chemical properties
(b) mental properties
(c) physical properties
(d) physico-chemical properties

Question : A change of state from one form to another is a

(a) physical change
(b) chemical change
(c) biological change
(d) state variation

Question : Which of the following is an irreversible change ?

(a) Physical
(b) Rusting
(c) Chemical
(d) None of these

Question : The chemical name of baking soda is:

(a) hydrogen carbonate
(b) calcium carbonate
(c) sodium hydrogen carbonate
(d) none of these

Question : Condensation of steam is not a:

(a) chemical change
(b) physical change
(c) rusting
(d) both (a) and (c)

Question : The shipping industry has to bear huge financial loss because of rusting of ships. The rusting of ships occur because:

(a) the body of ship is always in contact with water.
(b) the air around the ship is humid.
(c) presence of salts in sea water speed up the process of rusting.
(d) All of the above

Question : Few example of chemical changes are:

(a) burning of coal
(b) food getting spoiled
(c) formation of curd
(d) all of these

Question : The process of depositing a layer of zinc over iron is known as

(a) aluminisation
(b) galvanisation
(c) fertilisation
(d) ironing

Question : How crystal of pure substances are obtained?

(a) By crystallization
(b) By chromatography
(c) By peptization
(d) By all these methods

Question : A chemical change may bring

(a) evolution of gas
(b) change in colour
(c) change in taste
(d) all of these

Question : In chemical change

(a) Change is reversible
(b) Molecules of a substance change
(c) Molecules of the substance do not change
(d) Substance remain same

Question : Which of the following is an irreversible change ?

(a) Physical
(b) Rusting
(c) Chemical
(d) None of these

Question : 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

Question : Which property stays the same during physical and chemical changes?

(a) Density
(b) Shape
(c) Mass
(d) Arrangement of particles

Question : Properties like size, shape, colour, state of a substance are

(a) chemical properties
(b) mental properties
(c) physical properties
(d) physico-chemical properties

Question : Ships suffer a lot of damage from rusting inspite of being painted because:

(a) sea water contains many salts
(b) sea water is bitter
(c) sea water is sour
(d) sea water is sweet

Question : Which of the following is a chemical change?

(a) Dissolving of common salt into water
(b) Changing of water into ice
(c) Melting of ice
(d) Rusting of iron

Question : How crystal of pure substances are obtained?

(a) By crystallization
(b) By chromatography
(c) By peptization
(d) By all these methods

Question : A change in which the original substance can be obtained back by change of conditions is called:

(a) reversible change
(b) physical change
(c) chemical change
(d) Both (a) and (b)

Question : 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

Question : Rusting occurs when iron is exposed to

(a) oxygen and water
(b) soil and rain
(c) breeze and sunlight
(d) salt water and clouds

Question : Formation of a compound is

(a) Temporary change
(b) Physical change
(c) Chemical change
(d) Reversible change

Question : For rusting:

(a) Only moisture is required
(b) Only air is required
(c) Both air and moistured are required
(d) None of these