Lesson26KeeptheCandleBurning

1、Lesson 26Keep the Candle Burning!,a candle,What do we need to do the experiment?,a candle holder,a big glass jar,a shallow dish,some water,a match,matches,a lighter,How to do the experiment?,1) Put the candle in the candle holder.,2) Put the candle holder on the dish.,3) Fill the dish half full with

2、 water.,4) Light the candle.,5) Let the candle burn for two or three minutes.,6) Carefully put the jar over the candle until the top of the jar rests on the dish.,7) Examine the water in the jar. What can you see ?,1)The candle stops burning.,Because it has used up all the oxygen in the jar.,why ?,W

3、hat makes the candle burn?,Oxygen,2)The water inside the jar rises. Why?,Because it uses the oxygen in the jar as the candle burns. When the candle stops burning, it has used up all the oxygen in the jar.,How far did the water rise?,One fifth of the jar.,Why ?,Because one fifth of the air is made up

4、 of oxygen, the water rises and fills about one fifth of the jar.,one fifth,分子基，分母序，分子 1 ,分母加 S,three fourths three quarters,one (a) quarter one fourth,one third,a (one) half one second (one-second),candle,candleholder,dish,fill,half,light,burn,uses,burning,up,1.You are very tired. Youd better stop

5、_(have) a rest. 2. What do you use to make a candle _(burn)? 3. You should put the jar over the candle _(careful). 4. He _(light) a candle and the room was bright.,to have,burn,carefully,lighted/lit,Practice:fill in the blanks with the correct form of the given words.,5. _(two), ask the students to

6、guess what will happen. 6. He kept the candle _(burn) for two hours. 7. Its time _(play) basketball. 8. What about _(go) for a walk?,Second,burning,to play,going,Homework:,Write an English composition according to the text. The title is “ An interesting experiment”.,Do an experiment after class. (课外实验拓展) Can an egg “swim” in the water? First, put some salt into the glass. Then, add some water. Next, mix the salt and the water together. Finally, put the egg into