2. Unit 13 The Water planet

3. The earth is a water planet.

5. _________ makes the ocean such a great place to live in.

7. Step 1. Preview Task ( 预习任务 ) be sensitive to mass and volume be measured in dissolved take advantage of become available to be frozen solid room temperature a freezing point keep …steady 对 … 敏感 质量与体积 以 …… 测量 溶解的 对 …… 加以利用 对 … 成为可能 被结成固体 室温 冰点 保持稳定

8. Structure of the passage 1 minute to skim the passage, focusing on the titles (title and subtitles)in the text and then fill in the chart below. You do not need to read the whole text. CHEMICAL STRUCTURE SALINITY THE PROPERTIES OF WATER DENSITY HEAT CAPACITY OCEAN MOTION

9. Chemical structure A metal spoon sinks into a glass （化学结构） of water Salinity W e put a bottle of hot water under the （盐度） quilt in winter and it will keeps us warm Density I f some oil goes into the sea by mistake, （密度） it will soon spread to quite an area Heat Capacity W e put a block of sugar into a glass of water and stir, and the whole glass of （热容量） water will become sweet Ocean Motion S alt water won’t freeze at zero （海洋运动） Step three: Match the facts with proper topics

10. Fast Reading Fast Reading Finding Topic Sentences

11. Topic Sentence of the text : Paragraph: ________ Sentence: Topic Sentence of SALINITY : Paragraph: ______ Sentence: Topic Sentence of CHEMICAL STRUCTURE : Paragraph: ________ Sentence: step one: step one: Finding Topic Sentences 7 3 2 Learning about the properties of water helps us understand life on our planet. The chemical structure of water makes it an excellent medium for life. The salinity of the earth's oceans is about thirty-five parts per thousand, meaning that there are about thirty-five grammes of dissolved solids and gases in one kilogramme of water.

12. Topic Sentence of HEAT CAPACITY : Paragraph: ________ Sentence: Topic Sentence of DENSITY : Paragraph: ________ Sentence: 4 The density of pure water is 1,000 kg/m3, meaning that one cubic metre of water weighs one thousand kilogrammes. 5 Heat capacity is the mount of energy it takes to raise the temperature of a substance by one degree centigrade. Topic Sentence of OCEAN MOTION : Paragraph: ________ Sentence: 6 Since changes in salinity and temperature affect water's density, the water in the ocean is always moving.

13. Step two:True or false 1. There are about five billion species in the oceans ranging from the tiniest plankton to giants like sharks and whales. ( ) 2. The water molecule is made of two hydrogen atoms and one oxygen atom. ( ) F F billion --- million made of --- made up of

14. 3. Pure water has a higher freezing point and is lighter than salt water. ( ) 4. If a substance has a density 888kg/ m3, it will float on Water. ( ) 5. The heat capacity of water is relatively high, so most animals and plants don’t like living in the ocean. ( ) 6. The most important thing we can learn about water is that we must protect it and use it wisely. ( ) T T F T

15. Step three: Careful reading Some basic facts of each paragraph!

16. About 75 % ____ of the living space on earth is in the oceans. Marine life is incredibly_________________. 99% rich & varied 1.What percentage of the earth is covered by water?

17. There are about _____________species, _______________ the tiniest plankton _____giants like sharks and whales. 2. How many species are there in the oceans? five million ranging from to

18. * sea water (salt water) = ________________+ ________________+_________________ *The salinity of sea water affects: ___________ and_______________ dissolved gases dissolved solids pure water weight freezing point salinity of sea water: 35‰ 35% √ *It is made up of_______________&__________ *The water molecule is ______ * It has a slightly _______ and a slightly _________ end. *The normal state of water is__________ 2 hydrogen Atoms 1 oxygen atom polar positive negative liquid

19. Factors of density: ___________and ___________ Unit of density: _____________ = ___________________________. Density of pure water: _____________ = ________________________________________________ massvolume kg/m3 kilogrammes per cubic metre kilogrammes per cubic metre 1,000 kg/m3 1 cubic metre of water weighs 1,000 kilogrammes

20. *The heat capacity of water is ___________________. *Water can______ and _________heat without_________ the _____________of the oceans. How does the water move in the ocean? relatively high absorb Water is _____makes life possible. what Dense water sinks and less dense water is pushed to the surface. give off changing temperature

21. 1. Based on Para. 1, the author tells us that there are various species in the oceans, indicating that ____. A. Water plays a great role for marine life. B. Ocean is a good place for life. C. There are many reasons for tiniest plankton and giants like sharks and whales D. Ocean is part of the earth Step four: Reading Comprehension A

22. 2. The water in the ocean is always moving since _____. A.The temperature of sea water is relatively high. B. Water’s density affect changes in salinity and temperature. C. Changes in salinity and temperature have effect on water’s density. D. Waters in rivers always flow into the ocean. 3.Generally speaking, most animals & plants are ______ to large or suddenly changes in temperature. A.generous B. objective C. subjective D. sensitive C D

23. Seen from the space, the earth is an ______ planet. Water is very important to life. It is said that life on the planet began in the ______. Marine life is _________ rich. Life in the oceans _________ from the tiniest ___ ____ ___up to giants like _____and ____. The water molecule ___ _____ ____ ___ 2 hydrogen atoms and 1 oxygen atom. Water exists in three states. It has a relatively high __________ point. ocean oceans incredibly ranges all the waysharks whales is made up of freezing Step five: summary Fill in the blanks

24. Salt water has a ________ freezing point and is ________ than fresh water. There are many _____ of marine life. There is life even on the ________ of the deepest oceans. The creatures on the ocean floor manage to survive without ________ and get _________ from other sources lower heavier species bottom sunlight energy

25. Post—reading

26. Retelling Step one: Retelling propertyWhat is it?What is it good for? chemical structure density 2 hydrogen atoms and 1 oxygen atom It can break down both solids & gases and good for living things to live in the ocean,especially... It helps small creatures to float. Density is the relationship between mass and volume.

27. PropertyWhat is it?What is it good for? heat capacity ocean motion It is the amount of energy it takes to raise the temperature of a substance one degree centigrade. It keeps the oceans and the earth at a steady temperature The circulation adds energy to marine ecosystem and moves nutrients around. It’s the movement of water caused by changes in salinity & temperature.

28. Para.1 Marine life chemical structure Para.2 salinity Para.3 Density Para.4 Heat Capacity Para.5 Ocean motion Para.6 1. How is the text organized? Para.7 The importance of protecting water Step two: Discussion 2. Why is water important? water

29. 1. Review the properties of water. 1. Review the properties of water. 2. Finish some work on your workbook 2. Finish some work on your workbook