(a) Pure Elements (b) Pure Compounds (c) Mixtures. (a) Compound (b) Homogeneous Mixture (c) Heterogeneous Mixture

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1 KENDRIYA VIDYALAYA,IIT CAMPUS HOLIDAY WORKSHEET FOR CLASS : 6 SCIENCE SEPARATION OF SUBSTANCES Multiple choice questions (Choose the correct option) (A) Most of the substances we see around us are (a) Pure Elements (b) Pure Compounds (c) Mixtures (B) A solution of salt in water is a? (a) Compound (b) Homogeneous Mixture (c) Heterogeneous Mixture (d) Element (C) The property used in separating a mixture of two solids by winnowing is (a) difference in color (c) difference in weight (b) difference in size (d) Attraction by magnet (D) Which method is used to obtain pure liquid from a solution? (a) Distillation (c) Filtration (b) Condensation (d) Loading (E) Which of the following can dissolve in water? (a) Only Solids (c) Solids, liquids & gases (b) Only solids and liquids (d) only liquids Q.2 What is separation? Q.3 Why the separation of substances is necessary? Q.4 What is the basis of separation of components of mixture?

2 Q.5 When do we use hand picking as the method of separation? Q.6 What is threshing? How is it done? Q.7 Define winnowing? What is the principle of using winnowing as method of separation? Q.8 Where do we find sieving as the method of separation? Q.9 You are given a mixture of sand, salt and iron filling. Suggest some methods for separating all the components of this mixture? Q.10 Define filtration? Give 3 examples where filtration method is used. Q.11 What is evaporation? Where do we use this method at home? Q.12 What method is used to separate salt from sea water and how? Q.13 In which cases handpicking is enough as a method of separation? Q.14 One method of separation is not enough. Comment. Q.15 Differentiate between a pure substance and a mixture. Q.16 Is the separation of two immiscible liquids using separating funnel same as decantation? Q.17 What do you use to remove discarded tea leaves from tea? FILL IN THE BLANKS CHANGES AROUND US 1. The changes that can be reversed are called changes. 2. The changes that cannot be reversed are called changes. 3. On heating, the metals 4. On cooling, the metals 5. Burning of incense stick is an change. 6 On heating metal rim and fits into the wooden wheel. CHOOSE THE CORRECT ANSWER

3 1 Ripening of fruit is a ( reversible / irreversible ) change. 2 In ( reversible / irreversible ) change we cannot get back the original components. TRUE OR FALSE 1. Growing of trees is an irreversible change. 2 Formation of curd from milk is a reversible change. NAME THE FOLLOWING 1 Name any two reversible changes. 2 Name any two irreversible changes. DISTINGUISH BETWEEN Reversible and Irreversible changes CLASSIFY THE FOLLOWING CHANGES INTO REVERSIBLE AND IRREVERSIBLE CHANGES 1 Crumpling of paper 2 Burning of paper 3 Sawing of wood 4Cooking of food 5 Change of water into water vapour 6 Ironing of clothes Body Movements 1) Which system forms the supporting framework of the body? 2) Do snakes have legs? 3) Give example of an immovable joint or fixed joint? 4) Where do we find Ball and socket joints in our body?

4 5) Where do we find Hinge joints in our body?... Electricity And Circuits I. Fill in the blanks: 1. The electric energy which is supplied in our home comes from electric houses. 2. Diesel is generally used in big factories or at public functions as a standby. 3. The battery is uses at homes, offices and hospitals. 4. The tiny coiled wire which is supported by two thick wire inside the bulb is called - 5. Electric cell is a device which converts energy of chemicals energy. II. Name the following: 1. A combination of two or more cells 2. An electric device which converts electric energy into light energy 3. An electric circuit in which path of electricity is broken at some point is called III. Choose the correct answer: 1. An electric bulb has (two/one) terminals. 2. The base of an electric cell is its (negative/positive) terminal. 3. All metals are (conductors/insulators) of electricity. IV. Distinguish between Conductors and Insulators. V. Name the five transformations of electric energy. The Living organisms and their surroundings 1. Fill in the blanks a) The surroundings where organisms live is called. b) Ponds and lakes are examples of habitat. c) Air, soil and water are components. d) is an example of desert plant. 2. List any three characteristics of living things? 3. Name the organ through which fish breathes? 4. Write biotic components of the habitat?

5 5. Write abiotic components of the habitat? 6. Give two examples each of following a) Marine animals......, b) Desert animals......, c) Desert plants......, d) Mountain animals......, e) Floating plants......, f) Grassland animals......, 7. Draw a desert plant or a marine animal _