, solids, liquids, gases, metals and non metals, lustre, sonorous, malleable, homogenous mixture, heterogeneous mixture, hand-picking, winnowing, threshing, sieving, sedimentation, decantation, filtration and evaporation
1. How do pure substances and mixtures compare?
2.How can matter be classified?
3. How is matter classified?
4. How can mixtures be separated?
- Which of the following is a good conductor of heat? a) wood b) glass c) graphite d) rubber
- Butter paper is: a) transparent b) translucent c) opaque
- Copper metal: a) never rusts b) is a good conductor of electricity c) is a poor conductor of heat d) all of these
- A substance that allows the heat to pass through it is called: a)luster b) conductor c) opaque d) insulator
- Select the magnetic material a) Iron vessel b) polythene c) balloon d) aluminum
- _______ is a mixture of two or more materials. a) solubility b) solvent c) solution
- Which of the following is an important fuel? a) carbon dioxide b) natural gas c) helium d) oxygen
- Iron is separated from the mixture by: a) magnetic separation b) sedimentation c) winnowing d) sieving
- The process of settling down of the particles of an insoluble solid in a liquid is called: a) decantation b) sedimentation c) winnowing d) sieving
- Air is a: a) pure substance b) heterogeneous mixture c) the compound of oxygen and nitrogen d) homogeneous mixture
- The process of changing vapor into its liquid is called: a) condensation (b) loading (b) winnowing (d) evaporation
- List three properties of mixtures.
- Describe the process called loading.
- (a) State one use of the method of winnowing.(b) Give one use of the ‘handpicking’ method of separating mixtures in daily life.
- What is winnowing?
- What is the saturated solution?
- Name the process by which water is separated from rice and pulses after washing them.
- Which method is usually used to separate small pieces of stones from pulses at home?
- Define pure substances.
- Which substance is used for loading the clay particles suspended in muddy water?
- What are the various categories in which classification of materials takes place?
- What do you understand between Miscible and Immiscible liquids?
- Fill in the Blanks:
- Materials which contain two or more substances in any proportion are called——————.
- —————— mixtures are not uniform in appearance and composition.
- Cereals like wheat and rice are sources of————-.
- The process in which a liquid change into vapour is called———————–.
- —————— is a process of separating the component of substances from a liquid mixture by selecting evaporation and condensation
- Nails are made up of metal because it: a) shiny b) does not bend easily c) rusts
- Woods is used for matches because it: a) burns b) rots c) floats
- Which of the following is a heterogeneous mixture? a) a salt solution (b) a salt-pepper mixture (c) air (d) a fizzy drink
- Which of the following is a homogeneous mixture? a) mist b) a sand-water mixture c) an oil-water mixture d) a nitrogen-oxygen mixture
- Tiny pieces of stones are usually separated from pulses before cooking by the method called : a) threshing b) sieving c) hand picking d) winnowing
- Which of the following does not represent a characteristic of pure substance? a) It has a uniform texture throughout (homogeneous) b) It has fixed boiling or melting point c) It is made up of different types of particles d) It can be an element or a compound
- What are the characteristics of metals : a) Good conductors of electricity, and sonorous, solid at room temperature, transparent shine bright when polished b) Good conductors of electricity and heat; soild at room temperature, opaque except in extremely thin films; donot shine at all when polished c) bad conductors of electricity and heat; solid at room temperature opaque except in extremely thin films d) Good conductors of electricity and heat; solid at room temperature; opaque except in extremely thin films; shine brightly when polished
- Select and incorrect reason for separating components of a mixture: a) to separate two or more different but useful components b) to remove undesirable and useless components c) to remove pure or harmless components d) to obtain pure sample of a substance
- What happens if a saturated solution of sugar is cooled to a lower temperature?
- Do you agree with statement ‘sea water is a heterogeneous mixture’. Give reasons for your answer.
- Suppose your mother wants to remove pieces of vegetables from a large quantity of soup. Find out how she can do that quickly?
- There are four mixtures A, B, C and D. The mixture A contains sand and sugar, mixture B contain chalk powder and salt, mixture C contains salt and sugar, whereas mixture D contains sugar and charcoal powder. Which one of these mixtures cannot be separated by using water as a solvent? Why
- How will you separate a mixture of common salt, sand and iron filings?
- Explain with the help of a diagram how can a mixture of oil and water be separated?
- Define solubility of a substance. How does the solubility of a substance vary with temperature?
- What do you mean by immiscible liquids? How are they separated?
- Why is sorting or classification of materials important?
- Material C is stretchy but not an absorbent. Material D is a good absorbent but does not stretch. Which will make the best swimwear? a) Material D b) Material C c) material C and make good swimwear.
- A solid substance is dissolved in water. Which of the following methods is used for separating it?
(a) distillation (b) evaporation (c) filtration (d) decantation
- Oil and water can be separated through a) filter paper b) distillation c) evaporation d) separating funnel
- Why do you often need to separate mixtures into their components?
- Three groups of mineral are given below: Group 1: Salt, sugar , flour Group 2: Copper, Gold, Silver Group 3: Petrol, Kerosene, paper Identify the property common to each group:
a) Group 1- Solid Group 2- Bad conductors of heat Group 3- Liquid
b) Group 1- Edible Group 2- Non Metallic Group 3- Inflammable
c) Group 1- Edible Group 2- Metallic Group 3- Inflammable
6. Match the column I with column II and select the correct option from the codes given:
Column I Column II
P Chalk- Water i) A gaseous mix- mix
Q Glucose solution ii) Solid- gas mix
R Fizzy drink iii) Homogeneous solid- liquid mix
S Smoke iv) A heterogeneous solid liquid mix
T Air v) A gas- liquid mix
a) P-iii Q-iv R-v S-i T-ii b) P-v Q-iii R-iv S-ii T- i c) P-ii Q-i R-iv S-v T-iii d) P-iv Q-iii R- v S-ii T-i
- Which of the following statement is / are correct: Statement 1: Larger solid particles can be separated from smaller ones by filtration Statement 2: Cream can be separated from milk by churning Statement 3: A mixture of mud and water can be separated by loading, sedimentation and decantation Statement 4: Grains can be separated from stalks by threshing. Choose the correct option: a) I and II only b) II and IV only c) I, II and III d) II, III and IV only
- Take 10 ml of water in 6 test tubes each and add different samples of substances to each test tube. Shake the test tube vigorously for a couple of seconds and them undisturbed for 5 minutes. In which of these test tubes, sample substance will remain insoluble in water. Test Tube 1= Sugar Test Tube 2= Salt Test Tube 3= Sand Test Tube 4= Chalk Powder Test Tube 5= Saw dust Test Tube 6= Washing powder Choose the correct options: a) 1,2 and 3 b) 2,3 and 4 c) 3,4 and 5 d) 4, 5 and 6
- A few statement about centrifugation method are given below: Statement 1: The mixture containing very small suspended particles is rotated at a high speed in centrifugal machine Statement 2: The denser particles stay at the top Statement 3: The method is used to separate water from wet clothes in a washing machine Statement 4: The method can be used in lab for separating plasma and platelets. Choose the correct options: a) Statement 1 and 4 only b) Statement 1, 2 and 3 only c) Statement 2,3 and 4 only d) Statement 1,3 and 4 only
- Depending on nature of constituents present in a mixture, Seema suggested some methods of separation as shown in the table:
Type of Mix Method of separation
- Solid- solid handpicking and sieving
2. Solid- Liquid (insoluble) Sedimentation, decantation, filtration
3. Liquid-Liquid (immisicible) Decantation, separating funnel
4. Solid- Liquid (soluble) Filtration, Decantation
5. Liquid- Liquid (Miscible) Distillation
Choose the correct the option: a) Only 1 and 2 b) Only 3 c) Only 1 and 5 d) Only 4
- A science teacher labelled 3 glass slide P,Q,R. She painted Q with light blue color, R with black and P was left as such. Then she asked students to put slide on white paper with X mark. Students will be see the mark clearly ( partially) a) P,Q b) P,Q,R c) P, R d) None of the above
- Study the given table showing some daily used items which can be made from more than one material.
Items Wood Plastics Metals Glass
- Cooking pot Yes Yes X X
- Storage container Yes Yes Yes Yes
- LPG Cylinder Yes Yes X Yes
- Tea Cup Yes Yes Yes X
Which of the following is incorrect: a) 1 and 4 b) 1,3 and 4 c) 1 and 3 d) 2 and 3