E. Fill in the blanks :
1. Germs can be killed by adding ......
tablets to the water.
2. ....is used to cool the water vapour in Distillation.
3. Distilled water is the ......
form of water.
4. .......is obtained from sea water by the process of
F. Short Answer Type Questions :
1. Differentiate between sedimentation and decantation.
2. Name any five pure
substances.
3. Define threshing
4. Give any two properties of mixtures.
G. Long Answer Type Questions :
1. What is filteration? Elaborate with the help of an example.
2. Describe the term evaporation. How is salt prepared from sea water
3. Why do we use a filter paper?
4. Give some examples of mixtures used in our daily life.
Answers
Answer:
E.fill in the blanks
1.chlorine
2.Condenser
3.Purified
4. salt
F.Short answers
1.Sedimentation is the process of settling down of heavy insoluble impurities. ... Decantation is followed by sedimentation. Decantation is the process by which sedimented liquid is seperated by pouring it in the other container very slowly without disturbing the setteled sediments at the bottom of the container.
2. Gold,copper,oxygen,diamond and sugar
3. Threshing is the process of separation of grain from the stalk on which it develops and from the chaff or unit that covers it.
4. • Mixure can be homogeneous
• The proportions of the substances vary in an indefinite manner
G.Long answers
1. The most common example is making tea. While preparing tea, a filter or a sieve is used to separate tea leaves from the water. Through the sieve pores, only water will pass. The liquid which has obtained after filtration is called the filtrate; in this case, water is the filtrate.
2. the act or process of evaporating: a : change from a liquid to a vapor evaporation of water . But warming increases the evaporation of ocean water, which could increase the snowfall on the Arctic and Antarctic ice sheets, remove water from the ocean, and lower sea level. One of them is common salt, when sea water is allowed to stand in shallow pits, water gets evaporated by sunlight and slowly turns into water vapor. In a few days, the water evaporates completely leaving behind the solid salts. Common salt is then obtained from this mixture of salts by further purification.
3. Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine substances from liquids or air. It is used in science labs to remove solids from liquids. This can be used to remove sand from water.
4. •Oil and water.
•Lemon juice and tea.
•Honey and tea.
•Milk and chocolate.
•Coffee and cream.
•Cream and sugar.
•Flour and butter.
•Cereal and milk.