Separation of Substances Class 6 Questions and Answers

Science is the process of acquiring new knowledge through observation and experimentation. Science always leads to new discoveries, which leads to more questions, new mysteries and something else that needs explaining. It can help us to understand ourselves and our world to recognise how it works and where we fit within it. 

Separation of Substances is the fifth chapter in the Class 6 Science syllabus. This lesson deals with the reasons for separating substances and methods of separation. Separation of substances should be done to remove impurities or to get two or more useful products. There are various methods for separating substances, such as threshing, handpicking, winnowing, sieving, sedimentation, decantation, filtration, evaporation, etc. You will learn all these methods in Class 6 Science Chapter 5.

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Our experienced teaching faculty has developed the most reliable study and practice materials such as NCERT solutions, CBSE revision notes, CBSE sample papers and more to help students grasp all the concepts of the chapter easily. 

The Extramarks team understands the importance of students revising the chapter by solving questions. Hence, our team of Science teachers have prepared a comprehensive list of Class 6 Science Chapter 5 Important Questions taken from the NCERT textbook, NCERT exemplars, CBSE past years’ question papers, and other reference books, etc., for students to help revise the topics thoroughly and score well in the examination.

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Important Questions Class 6 Science Chapter 5 – With Solutions

Students are constantly advised to solve important questions for each chapter to understand the concepts better. Extramarks’ Important Questions Class 6 Science Chapter 5 have been made keeping in mind all the requirements of students. Extramarks important questions make students ready for their examination. 

Mentioned below are a few questions and their solutions from our Important Questions Class 6 Science Chapter 5.

Question 1. What is winnowing? Where is it used?

Answer 1: Winnowing is the process of using wind or air blowing to separate heavier and lighter components of a mixture. Farmers use this method to separate lighter grain husk fragments from heavier grain seeds.

Question 2. How will you separate sand and water from their mixture?

Answer 2: Sand and water will be separated using the decantation and sedimentation methods. First, we leave this mixture for some time. The heavier sand eventually settles to the bottom after some time. The mixture will separate once we pour water into another container.

Question 3. Fill in the blanks:

(a) 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 ____________.

(b) The process of obtaining salt  from sea water is called 

____________ .

(c) When milk, cooled after boiling, is poured onto a piece of cloth, the cream (malai) is left behind. This process of segregating cream from milk is an example of ______. 

(d) The method of separating seeds of paddy from its stalks is called  ____________.

Answer 3: 

(a) sedimentation and decantation

(b) evaporation

(c) filtration

(d) threshing

Question 4. Name the process by which we get salt from ocean water.

Answer 4: Evaporation is the process by which we get salt from ocean water.

Question 5. What is Sieving? Where can it be used?

Answer 5: Fine particles are separated from larger particles during the sieving process using a sieve. It is utilised on building sites or in grain mills. Wheat contaminants like husks and stones are eliminated in the flour mill. Sand is sieved to remove stones and pebbles.

Question 6. A mixture of iron nails, salt, oil and water is provided to you. Give stepwise methods to separate each component from this mixture.

Answer 6: A mixture of iron nails, salt, oil and water can be separated by the following steps:

• Iron nails can be picked out by hand or using a magnet.
• By using a separating funnel or decantation, remove the oil.
• Using evaporation, evaporate the salt and water mixture. Salt is left behind when water is condensed again.

Question 7. What is centrifugation?

Answer 7: Centrifugation is the process of separating a mixture through spinning. Skim milk from whole milk, water from your clothes, and blood cells from your blood plasma are separated using it.

Question 8. Name and describe briefly a method which can help separate a mixture of husk from grains. What is the principle of this method?

Answer 8: Winnowing is a method for removing the husk from grains. The lighter husk gets carried away by air and falls to the earth when the mixture is allowed to fall from a height. This technique is based on the idea that the wind will carry lighter particles away in a mixture of different weighted components.

Question 9. What is a strainer?

Answer 9: A strainer is an object with holes through which a liquid is poured to separate the liquid from any particles.

Question 10. Name the process used to separate cream from curd.

Answer 10: Centrifugation is the process used to separate cream from curd.

Question 11. 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 11: (b) Evaporation

Explanation: Water evaporates during the evaporation of the copper sulphate solution, leaving solid copper sulphate behind.

Question 12. List some materials that are used as filters.

Answer 12: 

• Cotton
• Filter paper
• Sand
• Charcoal
• Muslin cloth

Question 13. Define the term handpicking.

Answer 13: Handpicking is the method of manually removing slightly larger particles from a mixture. For instance, handpicking can be used to separate stone fragments from grains of rice or wheat.

Question 14. Paheli bought some vegetables such as french beans, lady’s finger, green chillies, brinjals and potatoes, all mixed in a bag.

Which of the following methods of separation would be most appropriate for her to separate them?

(a) Winnowing

(b) Sieving

(c) Threshing

(d) Hand picking

Answer 14: (d) Hand picking

Explanation: Due to their large size, handpicking is the preferred way for separating the vegetables.

Question 15. What is the use of decantation?

Answer 15: Decantation is used to separate insoluble solids or liquids from the liquid. 

Question 16. Elaborate on the process of filtration.

Answer 16: The filtering process involves removing an insoluble material from a liquid using a filtering medium, such as filter paper, cloth, a strainer, etc. The liquid free of suspended debris flows through the filter paper and is collected as filtrate. At the same time, the solid, insoluble substance is held on the filter paper as residue. The steps of evaporation and crystallisation can separate some soluble infiltration components.

Question 17. Four mixtures are given below.

(i) Kidney beans and chickpeas

(ii) Pulses and rice

(iii)  Potato wafers and biscuits

(iv) Rice flakes and corn

Which of the following 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 17: (d) (iii) and (iv)

Explanation: Mixtures of rice flakes and corn and potato wafers and biscuits can be separated by winnowing because there is a difference in the weight of the two components, one being lighter and the other being heavier.

Benefits of Solving Important Questions Class 6 Science Chapter 5

Students need to practice more and more questions to improve their marks in the Science exam. The more they practise, the better they will write answers and also increase their understanding of different Science topics. Our expert faculty members at Extramarks identify the key factor in scoring better marks in exams. That’s why they have prepared this question series that can provide students with a wide range of questions. They have also written step-by-step explanations with detailed answers to the questions. 

There will be multiple benefits if students solve the Important Questions Class 6 Science Chapter 5 for their exams. Some of these are given below:

• Our question bank helps you to know the paper pattern, which is very important to save time during your examination. When you solve more questions, you tend to improve your speed, boosting your score.
• Solving Science Class 6 Chapter 5 important questions lets you know your weaknesses and strengths. Then it would help if you worked more towards your weaknesses.
• Solving Chapter 5 Class 6 Science Important Questions aids in the proper management of time. Solving as many papers as possible aids in strengthening one’s grip on the subject. This keeps one well abreast with solving different questions in the least time without worrying about losing marks or leaving any questions unattempted.

Extramarks provide learning solutions and important questions for students from Class 1 to Class 12. We have abundant resources available on our website. Students can click on the links given below to access some of these resources:

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