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You are provided with a mixture of salt, sand, oil and water. Write the steps involved for the separation of salt, sand and oil from the mixture by giving an activity along with the diagram.

Answer: A mixture of salt, sand, oil and water can be separated by using these steps: 1. Decant the oil from the mixture which is floating. Hence... View Article

Read the story titled “WISE FARMER” and tick the correct option to complete the story. A farmer was sad/happy to see his healthy wheat crop ready for harvest. He harvested the crops and left it under the sun/rain to dry the stalks. To separate the seeds from the bundles of the stalk he handpicked/threshed them. After gathering the seed grains he wanted to separate the stones and husk from it. His wife winnowed/threshed them to separate the husk and later sieved/handpicked to remove stones from it. She ground the wheat grains and sieved/filtered the flour. The wise farmer and his wife got a good price for the flour. Can you tell why?

Answer: (i) Happy (ii) Sun (iii) Threshed (iv) Winnowed (v) Handpicked (vi) Sieved A farmer was happy to see his healthy wheat crop ready for... View Article

Paheli was feeling thirsty but there was only a pot of water at home which was muddy and unfit for drinking. How do you think Paheli would have made this water fit for drinking if the following materials were available to her. [Alum, tub, muslin cloth, gas stove, thread, pan and lid.]

Answer: With the following materials available: alum, tub, muslin cloth, gas stove, thread, pan and lid Paheli could undertake the following... View Article

Both Sarika and Mohan were asked to make a salt solution. Sarika was given a teaspoonful of salt and half a glass of water, whereas Mohan was given twenty teaspoons full of salt and half a glass of water. 1) How would they make salt solutions? 2) Who would be able to prepare a saturated solution?

Answer: To make a salt solution, mix the salt in water and by continuous stirring results in a salt solution. Mohan will be able to prepare a... View Article

Match the mixtures in column I with their method of separation in column II.

Column I Column II (a) Oil mixed in water (i) Sieving (b) Iron powder mixed with four (ii) Hand-picking (c) Salt mixed with water (iii)... View Article

Name and describe briefly a method which can be helpful in separating a mixture of husk from grains. What is the principle of this method?

Answer: By using the process of winnowing, the husk can be separated from grains. When the mixture is allowed to fall down from a height, the... View Article

State whether the following statements are true or false. (a) A mixture of oil and water can be separated by filtration. (b) Water can be separated from salt by evaporation. (c) A mixture of wheat grains and wheat flour can be separated by sieving. (d) A mixture of iron filings and rice flour can be separated by a magnet. (e) A mixture of wheat grains and rice flakes can be separated by winnowing. (f) A mixture of tea leaves and milk can be separated by decantation.

Answer: (a) A mixture of oil and water can be separated by filtration. - False. Since a mixture of oil and water can be separated by a separating... View Article

Fill in the blanks with appropriate word. Filtration is helpful in separating an insoluble_from a.

Answer: Filtration is helpful in separating an insoluble solid from a liquid. Filtration is the most common method of separating a liquid from... View Article

Fill in the blanks with appropriate word. The process of settling of heavier particles is called_____.

Answer: The process of settling of heavier particles is called sedimentation. Sedimentation is defined as the separation process in which solids... View Article

Fill in the blanks with appropriate word. Husk from wheat flour is generally removed by______

Answer: Husk from wheat flour is generally removed by sieving. Sieving allows the fine flour particles to pass through the holes of the sieve... View Article

Fill in the blanks with appropriate word. ____ are obtained from stalks by threshing.

Answer: Grains are obtained from stalks by threshing. Threshing is the process that is used to separate the grain from stalks etc. In this... View Article

Fill in the blanks with appropriate word. Small pieces of stone can be removed from rice by_____.

Answer: Small pieces of stone can be removed from rice by handpicking. We come across many instances in our daily lives when we must separate... View Article

Sheela, Saima and Ravi have to dissolve the maximum amount of sugar in the same amount of milk so as to win in a game. Ravi took hot boiling milk while Saima took ice-cold milk. Sheela managed to get milk at room temperature. Whom do you think would win the game and why?

Answer: The solubility of solids in liquids increases with temperature. Ravi would win the game because he will be able to dissolve the maximum... View Article

Paheli asked for a glass of water from Boojho. He gave her a glass of ice-cold water. Paheli observed some water droplets on the outer surface of the glass and asked Boojho how these droplets of water were formed. Which of the following should be Boojho’s answer? (a) Evaporation of water from the glass. (b) Water that seeped out from the glass. (c) Evaporation of atmospheric water vapour. (d) Condensation of atmospheric water vapour.

Answer: (d) Condensation of atmospheric water vapour. The droplets of water were formed when the air reaches the surface of the ice-cold glass,... View Article

During summer, Boojho carries water in a transparent plastic bottle to his school. One day he left his bottle in the school. The bottle still had some water left in it. The following day, he observed some water droplets on the inner surface of the empty portion of the bottle. These droplets of water were formed due to (a) boiling and condensation (b) evaporation and saturation (c) evaporation and condensation (d) condensation and saturation.

Answer: (c) evaporation and condensation The water droplets were formed due to high temperature in summers; the water gets heated in a plastic... View Article

In the activity, a teacher dissolved a small amount of solid copper sulphate in a tumbler half-filled with water. Which method would you use to get back solid copper sulphate from the solution? (a) Decantation (b) Evaporation (c) Sedimentation (d) Condensation

Answer: (b) Evaporation To get back solid copper sulphate from the solution we can use the method evaporation. When the solution of copper... View Article

You might have observed the preparation of ghee from butter and cream at home. Which method(s) can be used to separate ghee from the residue? (i) Evaporation (ii) Decantation (iii) Filtration (iv) Churning Which of the following combination is the correct answer? (a) (i) and (ii) (b) (ii) and (iii) (c) (ii) and (iv) (d) (iv) only

Answer: (b) (ii) and (iii) Because the mixture is made up of two distinct materials in different states which is ghee is liquid and the residue... View Article

While preparing chapatis, Paheli found that the flour to be used was mixed with wheat grains. Which out of the following is the most suitable method to separate the grains from the flour? (a) Threshing (b) Sieving (c) Winnowing (d) Filtration

Answer: (b) Sieving By the method of sieving, flour can be separated from wheat grains due to the difference in the size of flour and grain. The... View Article

Four mixtures are given below. (i) Kidney beans and chickpeas (ii) Pulses and rice (iii) Rice flakes and corn (iv) Potato wafers and biscuits Which of these can be separated by the method of winnowing? (a) (i) and (ii) (b) (ii) and (iii) (c) (i) and (iii) (d) (iii) and (iv)

Answer: (d) (iii) and (iv) By using the method of winnowing, mixtures of rice flakes and corn, potato wafers and biscuits can be separated since... View Article

Which amongst the following methods would be most appropriate to separate grains from bundles of stalks? (a) Hand-picking (b) Winnowing (c) Sieving (d) Threshing

Answer: (d) Threshing To separate grains from bundles of stalks threshing is the best method. Threshing is the process of separation of grain... View Article

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