CBSE Class 6 Science Separation of Substances MCQs

Question. There are two beakers having oil and water as shown below. The oil is of a type that floats on water and does not mix with it. If all the water from the first beaker is poured into the beaker of oil, what will be the level in the second beaker?

Answer : B

Question. The set up shows an apparatus for filtration.This apparatus can be used for separating which of the following mixtures? 

a. salt and sugar

b. sugar and water

c. glucose and water

d. saw dust and water

Answer : D

Question. A mixture consists of 4 different components as shown here.It is passed through several layers of mesh plates whose sizes are given below.What will collect at the bottom of vessel?

Answer : D

Question. Which of these cannot be used to make water safer to drink?

a. Filtration

b. Boiling

c. UV Filtration

d. Refrigeration

Answer : D

Question. The apparatus used for purifying water using a method called 'distillation' is shown below. If Impure water is boiled and the steam formed is passed through a chamber. Why is the cold water also passed through this chamber?

a. The cold water removes the impurities.

b. The cold water helps the steam condense.

c. The cold water helps the water evaporate.

d. The cold water dissolves the steam.

Answer : B

Question. Salt dissolving in water can be called a REVERSIBLE CHANGE because_____________.

a. water changes from one form to another

b. salt can be recovered by evaporating the water

c. it is a chemical change

d. salt is available both in the powdered and crystal forms

Answer : B

Question. Ram filtered a jar of muddy water. Filtration helps Ram to _____________________.

a. remove particles which are not dissolved in water

b. bring about a change of colour in water

c. kill the germs in the muddy water

d. clean the water by adding a chemical to it

Answer : A

Question. Cold water and hot tea are kept in two identical glass vessels, each covered by a metal lid. After some time, water droplets are seen in both vessels. Where exactly are the droplets likely to be found in each case? 

a. A

b. B

c. C

d. D

Answer : C

Question. Rani wants to find out whether the temperature of water makes any difference to the rate at which salt dissolves. She has planned 6 set ups P, Q, R, S, T and U. Which TWO set ups above should she use?

a. P and R

b. Q and S

c. P and T

d. S and U

Answer : C

Question. Cold water and hot tea are kept in two identical glass vessels, each covered by a metal lid. After some time, water droplets are seen in both vessels. Where exactly are the droplets likely to be found in each case? 

a. A

b. B

c. C

d. D

Answer : C

Question. The night of July 31st, 2004 is a full moon night in Delhi. Will it also be a full moon night in Mumbai? In New York?

a. It will be a full moon night in both Mumbai and New York.

b. It will not be a full moon night in either Mumbai or New York.

c. It will be a full moon night in Mumbai, but not in New York.

d. It will be a full moon night in New York, but not in Mumbai

Answer : A

Question. Anita conducted a scientific experiment and reported the results. If Anita’s results are valid, then others in her class should be able to

a. perform the same experiment under the same conditions and obtain the same results.

b. perform the same experiment under the same conditions and obtain different results.

c. perform the same experiment under different conditions and obtain the same results.

d. perform a different experiment and obtain the same results.

Answer : A

Question. The Election Commission in India uses an indelible ink to mark the fingernails of voters as evidence of their having voted. This ink made of Silver Iodide and other pigments, leaves a mark on the cuticle of the nail as shown: What is the likely appearance of this indelible mark in the nail of the index finger after 3 months?

Answer : B

Question. Melting of ice to form water is called a reversible change because

a. water can dissolve almost everything

b. ice can be formed again by freezing water

c. water vapour can be formed by heating water

d. it is a chemical change

Answer : B

Question. A blanket keeps us warm. The time a cube of ice will take to melt will ______ if it wrapped in a piece of cloth from a blanket.

a. increase

b. decrease

c. stay unchanged

d. stay unchanged

Answer : A

Question. The technique that separates a liquid from an insoluble solid by carefully pouring off the liquid is called ____. 

a. Evaporation 

b. Decantation 

c. Filtration 

d. Distillation 

Answer : B

Question. The separation technique used to separate a solid‐solid mixture is ____. 

a. Decantation 

b. Evaporation 

c. Filtration 

d. Handpicking 

Answer : D

Question. Suppose you are making some tea, and have boiled water and added tea leaves to the water. Then you realize that you cannot find the strainer. You look for a clean piece of cloth, but do not find one. What method would you like to apply for a cup of tea without leaves 

a. Sieving 

b. Evaporation 

c. Decantation 

d. Filtration 

Answer : C

Question. Peanuts are separated from a mixture of peanuts and corn by ____. 

a. Sieving 

b. Winnowing 

c. Handpicking 

d. Threshing 

Answer : 

Question. The method used to separate sand and saw dust is: 

a. Threshing 

b. Winnowing 

c. Hand‐ picking 

d. Magnetic separation 

Answer : C

Question. Salt is obtained from sea water by drying it in the sun. The process is known as ‐_________. 

a. Filtration 

b. Evaporation

c. Sedimentation 

d. Condensation

Answer : B

Question. Methods used to separate a mixture of salt and sand is by treating the mixture with water and then: 

a. Filtration followed by evaporation 

b. Sedimentation followed by evaporation 

c. Filtration followed by condensation 

d. None of the above. 

Answer : A

Question. The method of separating seeds of paddy from its stalks is called ___________. 

a. Decantation 

b. Winnowing 

c. Threshing

d. Sedimentation

Answer : C

Question. When milk, cooled after boiling, is poured onto a piece of cloth the cream (malai) is left behind on it. This process of separating cream from milk is an example of ___________. 

a. Hand picking 

b. Filtration 

c. Churning 

d. Sedimentation

Answer : B

Question. Impurities settled at the bottom when muddy water was kept overnight in a bucket. The clear water was then poured off from the top. The process of separation used in this example is called ___________. 

a. Decantation 

b. Filtration

c. Sedimentation followed by decantation 

d. Evaporation

Answer : C 

Question. Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving sugar? In which case would it be possible to dissolve more sugar? 

a. Add sugar before cooling. 

b. Add sugar after cooling 

c. There will be no difficulty in dissolving sugar in either cold water or in hot water.

d. On adding ice the taste of the lemonade will change.

Answer : A

Question. The rate of sedimentation is increased by adding ____ to the water.

a. Salt

b. Sugar

c. Alum

d. Soap

Answer : C

Question. The process followed to separate grains form the stalks is called

a. Winnowing

b. Threshing

c. Sieving

d. Hand picking

Answer : B

Question. The process of increasing the rate of sedimentation in a suspension by adding some chemical is

a. Filtration

b. Crystallisation

c. Loading

d. Condensation

Answer : C

Question. The process of separating the constituents of a liquid by agitating it vigorously

a. Evaporation

b. Churning

c. Filtration

d. Sedimentation

Answer : B

Question. The method that is used to obtain pure salt from impure salt

a. Decantation

b. Crystallization

c. Evaporation

d. Condensation

Answer : B

Question. A solution which cannot dissolve more of a given substance at a given temperature is

a. Solution

b. Filtrate

c. Saturated solution

d. Unsaturated solution

Answer : C

Question. This harmful microbe in water causes typhoid and jaundice

a. Virus

b. Bacteria

c. Algae

d. Fungi

Answer : B

Question. Rain water is a kind of

a. saline water

b. distilled water

c. carbonated water

d. saturated water

Answer : B

Question. The method used to separate a dissolved solid component from its solution

a. Evaporation

b. Filtration

c. sedimentation

d. Decantation

Answer : A

Question. Butter is separated from curd by the process of

a. Filtration

b. Heating

c. Churning

d. Sieving

Answer : C

Question. A pure solid is obtained from its solution by the process of

a. Condensation

b. decantation

c. Sedimentation

d. Filtration 

Answer : A

Question. Separating the insoluble suspended solids of various sizes from a liquid is called

a. Filtration

b. Crystallization

c. Evaporation

d. Condensation 

Answer : A

Question. Cotton fibre is separated from cotton seeds by the process of

a. Churning

b. Boiling

c. Colouring

d. Ginning

Answer : D

Question. Principle behind winnowing is

a. Difference in densities of components

b. Difference in colours of components

c. Difference in appearance of components

d. Difference in shapes of components 

Answer : A

Question. Paneer is separated from curdled milk

a. Condensation

b. Filtration

c. evaporation

d. sedimentation

Answer : B

Question. The process due to which steam changes into liquid state on cooling

a. Decantation

b. Sedimentation

c. Filtration

d. Evaporation 

Answer : D

Question. Corn is separated from husk by the process of

a. Sieving

b. Winnowing

c. Churning

d. Handpicking 

Answer : B

Question. A mixture of sugar and water can be separated by

a. Filtration

b. Evaporation

c. Separating funnel

d. decantation 

Answer : B

Question. A saturated solution can dissolve more of a substance on

a. Cooling

b. Heating

c. Condensing

d. Evaporating

Answer : B

Question. To evaporate a liquid into its vapour, heat the liquid below its

a. Above its melting point

b. Below its boiling point

c. Below its melting point

d. Above its boiling point 

Answer : B

Question. The clear liquid obtained after filtration is called

a. Water

b. Filtrate

c. Solution

d. Residue 

Answer : B

Question. Alum is added to muddy water to

a. Hasten sedimentation rate

b. Remove colour

c. Kill bacteria

d. Impart a sweet taste

Answer : A

Question. The process of making particles of mud heavy with alum

a. Decantation

b. loading

c. Filtration

d. Condensation 

Answer : B

Question. The addition of bleaching powder to the water

a. Kills the microorganism

b. Feeds the microorganisms

c. Helps the microorganisms to grow

d. None of these 

Answer : A

Question. Separation of kerosene oil and water is done by

a. Decantation

b. Filtration

c. Condensation

d. Crystallisation

Answer : A

Answer Key