Chemistry: Pure substances and mixtures, separation of mixtures Class VI Skill: Recall Q1.Define the following: a)Pure substances b) Mixture c)Evaporation d)Crystallisation e)Alloy Q2. List two examples of Solid + Solid mixtures separated by sieving. Q3. Identify the technique of separation and label the parts A, B and C in the diagram given below. Q4. Write any two sublimable substances used in our daily life. Q5. Mention the methods of separation used to separate a mixture of stones, table salt and water in their correct sequence. . Skill: Comprehension and Analysis Q6. Categorize the following list as compounds and mixture. vinegar, gold, steel, baking soda, copper, milk, Q7. Iron and Sulphur on heating together formed iron sulphide. Describe why iron sulphide is considered as a pure substance? Q 8. Explain with reason: i. Honey and milk are not considered as pure. ii. Sea water is collected in shallow beds for commercial purpose. iii. Mixtures do not have specific set of properties. Q 9. Identify the separation method shown in the picture given below and write the principle of this separation technique. Q 10. Differentiate between the following pairs of terms on the basis of characteristics given in the brackets. i. Heterogeneous mixture and Homogeneous mixture (definition) ii. Distillation and Evaporation (principle) iii. Compound and mixture(example) Skill: Application Q 11. Why do farmers need blowing wind for separation of chaff from seed grains after harvesting and threshing of their crops? Q 12. What strategy you would develop to prevent the dust and particulate pollutants from entering the air conditioned room?