Class 7 Physical And Chemical Changes CBSE Questions & Answers

Class 7 · Physical And Chemical Changes

This is Science Class 7 Physical and Chemical Changes CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Which is an example of physical change?
  • A
    Tarnishing of copper
  • B
    Corrosion of metals
  • C
    Boiling of water
    Correct
  • D
    Burning of paper
2
What characteristic best describe the change during physical changes?
  • A
    Change in composition
  • B
    Change in forms
  • C
    Composition remain same
    Correct
  • D
    Loss in mass
3
What property remains same during physical and chemical change?
  • A
    Shape
  • B
    Mass
    Correct
  • C
    Colour
  • D
    Density
4
Which of the following is an example of physical change?
  • A
    A bud turning into flower
  • B
    Ripening of fruit
  • C
    Rusting of iron
  • D
    Boiling of water
    Correct
5
Which of the following is a physical change?
  • A
    Aluminium metal is pounded into thin sheet
    Correct
  • B
    Copper reacts with strong acid
  • C
    Iron oxidised into iron oxide
  • D
    Sodium metal reacts with water
6
When silver come in contact of Sulpher, Sulpher sulphide is formed that change the colour of silver. It is
  • A
    Periodic change
  • B
    Physical change
  • C
    Chemical change
    Correct
  • D
    Temporary change
7
Two solutions are mixed together to form a new solution in which heat is evolved. This tells that
  • A
    Chemical change is taking place
    Correct
  • B
    A gas is being evolved
  • C
    Solution are insoluble
  • D
    Physical change is taking place
8
Harsh want to experiment with sugar crystals. Which of the following causes a sugar cube to change only physically and not chemically?
  • A
    Dehydrating sugar crystals with sulphuric acid
  • B
    Chewing the sugar crystals ting it
  • C
    Crushing the sugar crystals and dissolving in water
    Correct
  • D
    Burning the sugar crystals
9
Which of the following is a reversible change?
  • A
    Burning of match stick
  • B
    Germination of seed
  • C
    Melting of ice
    Correct
  • D
    Changing of milk into curd
10
Khushi draws a picture on aeroplane on a piece of paper and folded into a paper plane. His brother Harsh ripen up the paper and throws into fire. Which of the following is an example of chemical change?
  • A
    Drawing on the paper
  • B
    Folding of paper in the shape of aeroplane
  • C
    Ripening of paper
  • D
    Burning of paper in fire
    Correct
11
Sea water is a
  • A
    Compound
  • B
    Mixture
    Correct
  • C
    Molecule
  • D
    Element
12
Metal hydroxides are basic in nature. So, magnesium hydroxide is chemically basic in nature.
  • A
    Salty
  • B
    Basic
    Correct
  • C
    Neutral
  • D
    Acidic
13
Metal oxide which is acidic as well as basic in nature are called
  • A
    Acidic oxide
  • B
    Bi-nature oxide
  • C
    Basic oxide
  • D
    Amphoteric oxide
    Correct
14
All physical changes are
  • A
    Permanent
  • B
    Irregular
  • C
    Irreversible
  • D
    Reversible
    Correct
15
Baking soda is added to vinegar solution, hissing sound is produce due to evolution of
  • A
    Carbon dioxide gas
    Correct
  • B
    Hydrogen gas
  • C
    Nitrogen dioxide gas
  • D
    Water vapour