Water A Precious Resource - Worksheets

 CBSE Worksheet-01

Class – VII Science (Water: A Precious Resource)

  1. Water is a
    (a) Mixture (b) Compound (c) Element (d) Solution
  2. Water is chlorinated to
    (a) Improve its taste (b) Kill germs (c) Soften it (d) Change colour
  3. There is acute water shortage due to
    (a) Overuse and misuse (b) Excess evaporation (c) Climate change (d) Global warming
  4. What percent of your body weight is water?
    (a) 50% (b) 60% (c)70% (d) 80%
  5. Match the following
    Column AColumn B
    a. Watermeloni. Solid form of water
    b. Human bodyii. Increase water-table
    c. Ground wateriii. 99%
    d. Snowiv.70%
    e. Rain water harvestingv. 0.59%
  6. Fill in the blanks.
    1. The water of oceans is _______ hence can not be used for drinking.
    2. Like air, forest, sun, _______ is also a natural resource.
    3. The water bearing layer of the earth is _______
    4. In India _______ sector is the major user of water.
    5. One of major reason for the scarcity of water is _______.
  7. What is water pollution? Write its main causes.
  8. What is ground water? Why ground water level is decreasing in cities?
  9. Why water is called universal solvent?
  10. So much of water available on our planet Earth, but why do we still feel a shortage of water?

CBSE Worksheet-01
Class – VII Science (Water: A Precious Resource)
Answer key

  1. b
  2. b
  3. a
  4. c
  5. (a) – (iii), (b) – (iv), (c) – (v), (d) – (i), (e)- (ii).
    1. hard
    2. water
    3. aquifer
    4. agricultural
    5. growing population.
  6. Addition of harmful substance in water bodies to change its chemical, physical and biological property is called water pollution. It is mainly caused by addition of industrial wastes and untreated sewage in water bodies.
  7. Ground water is that water which percolates down the earth from existing water bodies or during rain from ground surface. Ground water is decreasing rapidly due to increase in population which results in excessive consumption of ground water.
  8. A large number of substances dissolve in water so it is called universal solvent. A liquid that dissolve another substance (solute) to form solution is called solvent.
  9. 75% of our Earth is made of water but only 3% of it is fresh water. Hence only a fraction is fit for human consumption and we still feel a shortage of water. Most of the water that exists on the earth is in the seas and oceans which is highly salty.