Separation of Substances is Chapter 5 taken from JKBOSE Class 6 Science. The given post is about the Separation of Substances Class 6 Question Answers. You will get short notes and question answers in the chapter in this post. The previous post was about Chapter 4 Sorting Materials into Groups. Let’s begin:
Separation of Substances Class 6 Question Answers
Overview of Chapter
- METHODS OF SEPARATION
- Hand Picking.
- Sedimentation, Decantation, Filtration.
- Use of more than one method of separation.
- Can water dissolve any amount of substance?
Most of the things which we use in our daily life are mixtures. A mixture is made up of two or more substances mixed in any ratio. The constituent substances of a mixture retain their individual properties. There are instances when we have to separate substances from a mixture of substances. Separation of substances can be done for any of the below-mentioned purposes:
- To remove an unwanted component from a mixture.
- To obtain the desirable component from a mixture.
- To remove the harmful component from a mixture.
- To obtain the pure sample of a substance from a mixture.
Here are some commonly used methods for separating the components of a mixture:
- Hand Picking: It is the method of separating unwanted substances like small pieces of stones from rice wheat and pulses.
- Threshing: It is the process in which the stalks of crops like wheat and paddy are beaten to separate grains from them and the chaff covering the grains.
- Winnowing: It is the method of separating husk from grains with the help of wind. It is used separate heavier and lighter components of a mixture by wind or by blowing air. This method is used by farmers to separate lighter husk particles from heavier seeds of grain.
- Sieving: Sieving is a method of separating mixtures that have components of different sizes. The method of separating a mixture by using a sieve is called sieving.
- Sedimentation, Decantation and Filtration: Sometimes there are some mixtures where separation of substances is not possible using the above-mentioned methods. In the separation of substances from such mixtures, these methods of separation are used. These methods are often used collectively. Sedimentation is the processing of the settling of heavy particles of a mixture at the bottom of the vessel. The heavy solid particles settled at the bottom of the vessel are called sediment while the clear liquid above it is known as supernatant. Decantation is the process of transferring clean liquid above the sediment from one vessel to another. Filtration is the process of removing insoluble solids from the liquid using a filter.
- Evaporation: The process of evaporation is the conversion of water into vapours. It is used to obtain solid materials that are dissolved in water.
- Use of more than one method of separation: There are several mixtures which cannot be separated by using a single method of separation and we have to use more than one method of separation. For example, separating the mixture of sand and salt is done by using multiple methods of separation.
- Can water dissolve any amount of substance: Water cannot dissolve any amount of substance. It can dissolve only a certain amount of substance at a particular temperature.
Separation of Substances Class 6th Question Answers
1. Why do we need to separate different components of a mixture? Give two examples.
Ans. We need to separate different components of a mixture due to following reasons:
a) To separate and obtain two useful components. E.g. Separation of rice and husk.
b) To separate or remove non-useful components from useful components. E.g. Separation of tea leaves after making tea.
c) To remove or separate impurities or harmful components. E.g. Separation of small pieces of stones from pulses.
2. What is winnowing? Where is it used?
Ans. Winnowing is a method used to separate lighter and heavier components of a mixture with help of wind or by blowing air. This method is commonly used by farmers to separate husk particles from grains of the crop.
When a mixture of grains (say wheat grains) and husk is allowed to fall down from a certain, the wind carries away the lighter husk particles while heavier grains fall down vertically and are separated from husk particles.
3. How will you separate husk or dirt particles from a given sample of pulses before cooking?
Ans. We can separate the husk and dirt particles from the given sample of pulses by using two methods. If the size of the particle is larger it can be done by handpicking but if the size of the particles is small, it can be done by the method of winnowing.
4. What is sieving? Where is it used?
Ans. Sieving is a method of separating components of different sizes from a given mixture of substances with the help of a sieve (coarse cloth, filter paper or mesh). It is commonly used to separate fine particles of wheat from bigger particles of husk.
5. How will you separate sand and water from their mixture?
Ans. The sand and water are separated from the mixture by using the process of sedimentation and decantation.
Sedimentation: In this process, the given mixture of sand and water is allowed to stand undisturbed for quite some time. The sand particles being heavier settles down at the bottom of the beaker.
Decantation: Now the clear water above the sand is poured gently into another vessel. In this way, sand and water are separated from their mixture.
6. Is it possible to separate sugar mixed with wheat flour? If yes, how will you do it?
Ans. Yes, it is possible to separate sugar mixed with wheat flour. As the particles of sugar are bigger than the fine particle of wheat flour. It can be separated easily by using the process of sieving.
7. How would you obtain clear water from a sample of muddy water?
Ans. It can be done in two ways:
First method: – When a sample of muddy water is allowed to pass through a filter paper having fine pores. The particles of sand and clay will remain on the filter paper and clear water is obtained in the beaker or tumbler.
Second Method: – In this method, a piece of alum is used to load the fine particles of clay which become heavier and settles down at the bottom. The clear water is decanted.
- Fill in the blanks
- The method of separating the seeds of paddy from its stalks is called _________.
- 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 _________.
- Salt is obtained from seawater by the process of _________.
- 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 _________.
- The method of separating the seeds of paddy from its stalks is called threshing.
- 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 filtration.
- Salt is obtained from seawater by the process of evaporation.
- 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 decantation.
- True or false?
- A mixture of milk and water can be separated by filtration. (False)
- A mixture of powdered salt and sugar can be separated by the process of winnowing. (False)
- Separation of sugar from tea can be done with filtration. (False)
- Grain and husk can be separated with the process of decantation. (False)
- 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?
Ans. Ice should be added to lemonade after dissolving sugar in it because the liquid’s solubility decreases with a decrease in temperature. If we add ice to the lemonade before dissolving sugar, it gets cool and will dissolve less sugar.
- Mustard oil gets accidentally mixed with water. How will you remove mustard oil from the water?
Ans. The mustard oil and water do not mix with each other because they are immiscible liquids. The oil is lighter than water and forms a separate layer above the water if a mixture of oil and water is allowed to stand for a while. Now, oil can be easily separated by using the process of decantation.
- A tiny iron drill of a carpenter falls into a heap of straw. Suggest a convenient way of recovering the drill.
Ans. The convenient way of recovering the drill is by using a large magnet. A large magnet has a higher magnetic field and so the iron drill is easily attracted to it when a magnet is brought near the heap of straw.
- Differentiate between a saturated solution and an unsaturated solution.
Ans. Saturated Solution: – The solution in which no more solute can be dissolved at a particular temperature is termed a saturated solution.
Unsaturated Solution: – The solution in which more of a solute can be dissolved at a given temperature is termed an unsaturated solution.
That’s all about the Separation of Substances Class 6 Question Answers. Hope it has helped. Do share your views about this post in the comment section below.
Leave a Reply