MCQ | NCERT Class 9 Science | Chapter 9: Methods of Separation in Everyday Life
Q1. Why do we separate different substances in our everyday life?
(a) To remove unwanted substances or obtain useful components
(b) To make all substances identical
(c) To increase the weight of substances
(d) To change every substance into a liquid
Answer: (a) To remove unwanted substances or obtain useful components
Q2. Which method is commonly used to separate stones from rice or pulses?
(a) Handpicking
(b) Filtration
(c) Evaporation
(d) Decantation
Answer: (a) Handpicking
Q3. Handpicking is suitable when
(a) the unwanted particles are large enough to be picked by hand
(b) the substances are completely dissolved
(c) the mixture contains only liquids
(d) the particles cannot be seen
Answer: (a) the unwanted particles are large enough to be picked by hand
Q4. Which method is commonly used to separate grains from stalks after harvesting?
(a) Threshing
(b) Filtration
(c) Evaporation
(d) Sedimentation
Answer: (a) Threshing
Q5. What is winnowing?
(a) Separating lighter components from heavier components using moving air
(b) Separating dissolved substances by heating
(c) Separating liquids using a filter
(d) Separating substances using a magnet
Answer: (a) Separating lighter components from heavier components using moving air
Q6. Which method can be used to separate husk from grains?
(a) Winnowing
(b) Filtration
(c) Evaporation
(d) Handwashing
Answer: (a) Winnowing
Q7. Why does winnowing work?
(a) Lighter particles are carried away more easily by moving air
(b) Heavier particles always dissolve in air
(c) All particles have the same weight
(d) Water separates the mixture
Answer: (a) Lighter particles are carried away more easily by moving air
Q8. What is sieving?
(a) Separating particles of different sizes using a sieve
(b) Separating liquids by boiling
(c) Separating dissolved substances using a magnet
(d) Separating gases using a filter
Answer: (a) Separating particles of different sizes using a sieve
Q9. Which of the following is an example of sieving?
(a) Separating bran from flour
(b) Separating salt from salt solution
(c) Separating oil from water
(d) Separating stones by hand
Answer: (a) Separating bran from flour
Q10. Which property is mainly used in sieving?
(a) Difference in particle size
(b) Difference in colour
(c) Difference in smell
(d) Difference in temperature
Answer: (a) Difference in particle size
Q11. What is sedimentation?
(a) Settling of heavier insoluble particles at the bottom of a liquid
(b) Dissolving a solid in water
(c) Changing liquid into vapour
(d) Separating two gases
Answer: (a) Settling of heavier insoluble particles at the bottom of a liquid
Q12. Which process usually follows sedimentation to separate the clear liquid from the settled particles?
(a) Decantation
(b) Winnowing
(c) Threshing
(d) Sieving
Answer: (a) Decantation
Q13. What is decantation?
(a) Carefully pouring out the clear liquid without disturbing the settled particles
(b) Heating a solution until the liquid disappears
(c) Separating grains from stalks
(d) Separating particles using moving air
Answer: (a) Carefully pouring out the clear liquid without disturbing the settled particles
Q14. Which method is commonly used to separate tea leaves from prepared tea?
(a) Filtration
(b) Winnowing
(c) Handpicking
(d) Threshing
Answer: (a) Filtration
Q15. What is filtration?
(a) Separating an insoluble solid from a liquid using a filter
(b) Separating two dissolved substances
(c) Separating grains using wind
(d) Separating substances by hand
Answer: (a) Separating an insoluble solid from a liquid using a filter
Q16. Which of the following mixtures can be separated by filtration?
(a) Sand and water
(b) Salt and water
(c) Sugar and water
(d) Salt and sugar
Answer: (a) Sand and water
Q17. Which method can be used to obtain salt from seawater?
(a) Evaporation
(b) Handpicking
(c) Sieving
(d) Winnowing
Answer: (a) Evaporation
Q18. What happens during evaporation?
(a) The liquid changes into vapour and leaves behind the dissolved solid
(b) The solid changes into a gas immediately
(c) The solid settles at the bottom
(d) The liquid becomes heavier
Answer: (a) The liquid changes into vapour and leaves behind the dissolved solid
Q19. Which method can be used to separate oil from water?
(a) Decantation
(b) Threshing
(c) Sieving
(d) Winnowing
Answer: (a) Decantation
Q20. Why can oil and water be separated by decantation?
(a) They do not mix and form separate layers
(b) Oil dissolves completely in water
(c) Water changes into a solid
(d) Both liquids have exactly the same density
Answer: (a) They do not mix and form separate layers
Q21. Which method is most suitable for separating iron filings from sand?
(a) Using a magnet
(b) Filtration
(c) Evaporation
(d) Decantation
Answer: (a) Using a magnet
Q22. Which property makes magnetic separation possible?
(a) Attraction of certain materials by a magnet
(b) Difference in taste
(c) Difference in smell
(d) Difference in temperature
Answer: (a) Attraction of certain materials by a magnet
Q23. Which method would be most suitable for separating a mixture of sand and water?
(a) Filtration
(b) Winnowing
(c) Handpicking
(d) Threshing
Answer: (a) Filtration
Q24. Which of the following pairs is correctly matched?
(a) Handpicking – stones from rice
(b) Winnowing – salt from water
(c) Filtration – husk from grain
(d) Evaporation – stones from pulses
Answer: (a) Handpicking – stones from rice
Q25. Which statement about separation methods is correct?
(a) The method of separation depends on the properties of the substances in a mixture
(b) Only one method can separate all types of mixtures
(c) Separation is possible only for solids
(d) All mixtures can be separated by filtration
Answer: (a) The method of separation depends on the properties of the substances in a mixture
