2019-2020年高二英语Unit13 Water and Ocean.doc

2019-2020年高二英语Unit13 Water and OceanTEACHING AIDS: puter, pictures, flash card.AIMS：To train the students to have love for the nature by knowing the properties of water and the present situation of water.PROCEDURES：Properties of water (group work)-reading passages-answering questions Preview: Two TasksTask One: Print the following picture and passage for the students to translate into Chinese as homework in the previous week.Water is a polar moleculeWaters unique properties are largely a result of its simple position and structure. As mentioned above, water is posed of two hydrogen atoms bound to one oxygen atom. As shown in your book, the two hydrogen atoms are smaller (the smallest atom there is, in fact) and they rest on both sides of the larger oxygen atom at an angle of 105? When the hydrogen atoms bine with oxygen, they each give away their single electron and form what is known as a covalent bond.Because electrons are more attracted to the positively charged oxygen atom, the two hydrogens bee slightly positively charged (they give away their negative charge) and the oxygen atom bees negatively charged. This separation between negative and positive charges creates what is known as a polar molecule, meaning a molecule that has an electrical charge on its surface somewhere. Although the water molecule as a whole has no charge, the parts of it, the hydrogen wings and the oxygen body, do exhibit individual charges.Task Two: Ask the students to form groups of four or five students to prepare the four experiments on Page17 . A WARMING UP：Play a game: The students will have a class without English Books. So play a game with them. Let them guess what the teacher will have them to learn. Here are some sentences which the teacher may use to have the students follow:T：I have something in my pocket. Can you guess what it is?Ss: Is it T:Its colorless; Its tasteless; Its odorless; It feels wet; Its distinctive in sound when dripping from a faucet or crashing as a wave; It dissolves nearly everything; It exists in three forms: liquid, solid, gas; It can absorb a large amount of heat; It sticks together into beads or drops; . Its part of every living organism on the planet. Ss: Its water!T: Yes! (show a globe to the students.) Whats this?Ss: Its the earth.T: What color is it?Ss: Its blue.T: Why is it blue?Ss: Because its covered by water.T: Yes, because two thirds of the surface of the earth is covered by water. Thats why our earth is called the water planet. (show paragraph one)Now how much do you know about water? In what ways can we use water?Ss: The students will do the experiments they have prepared once again in group form. When they are doing the experiments, they will explain to the audience in plain English.T: Ok. Let me show you more about water by some pictures. Look at the pictures. Then tell us in what ways we can use water.Speaking：Water can be used to make electricity.Water can be used to water fields.Water can be used to wash our food.Water can be use for industry /transport/ entertainment.Reading: Ask the students to read the passage for 10 minutes, then ask them to do the True or False exercise. Qs: 1. Water is polar, water is a liquid at room temperature; water has a high freezing point. The density of water is 1,000 kilograms per cubic meter.True.False.2. About three billion years ago, life on our planet began in the deep blue seas.True.False.3. Ninety-nine percent of the living space on earth is in the oceans.True.False.4. It is water that makes the ocean such a great place to live.True.False.5. Water can break down neither solids nor gases.True.False.6. Salinity is that dissolved gases and solids mix with pure water.True.False.7. The salinity of the Dead Sea is higher than that of any sea on the earth.True.False.8. Salt water has a higher freezing point and is lighter than pure water.True.False.9. When water freezes, its density doesnt change.True.False.10. Water can not absorb and give off a lot of heat without big changes in temperature.True.False.11. Less dense water sinks and dense water is pushed to the surface.True.False.Summary:Without water, there would be no oceans, no lakes, no rivers, no rain, no snow, no hail, no clouds, no polar ice caps, no Jolt cola, nothing to drink whatsoever, and probably no you, no me, no nothing! Water is everywhere; it defines our planet; it is intricately involved in just about every process on this planet in one way or another. Water rules!So you know how important water is being to us. We must pay more attention to the water resource. But the water resource is being polluted. (Show them pictures). How do you feel after seeing these pictures? Write an article about it. 板书设计：Unit 13 The Water PlanetWater can be used to 教学挂图make electricity.It is a good way to use w