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为了比较水和食用油的吸热本领的大小，小明做了如图所示的实验：在两个相同的烧杯中分别装有质量、初温都相同的水和食用油，用两个相同的酒精灯对其加热，实验数据记录如下表：

质量（g）升高10℃所需的时间（s）升高20℃所需的时间（s）升高30℃所需的时间（s）
食用油306489124
水3096163220
（1）在此实验中用______表示水和食用油吸热的多少．

（2）分析表中的数据可知：质量相同的水和食用油，升高相同的温度时，水吸收的热量______（填“大于、小于或等于”）食用油吸收的热量．

（3）如果加热相同的时间，______升高的温度更高．

（4）该实验中温度升高20℃时水吸收的热量为______J．[C水=4.2×103J/（kg•℃）]．

答案

（1）据上分析可知，酒精灯对其的加热时间越长，表明该物质所吸收的热量越多，故实验中用加热时间的长短表示水和食用油吸热的多少；

（2）质量相同的水和食用油，升高相同的温度时，水的加热时间长，故水吸收的热量多；

（3）据上面的分析可知，水的比热容要大于食用油的比热容，故据公式Q=cm△t可知，相同质量的水和食用油，若加热时间相同，即表明所吸收的热量相同，由于食用油的比热容小，故食用油的温度变化大，故其温度升的高；

（4）此时水所吸收的热量是Q=cm△t=4.2×103J/（kg•℃）×0.03kg×20℃=2520J．

故答案为：（1）加热时间长短；（2）大于；（3）食用油；（4）2520．

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Trip 1  One week in the Mountains

Bring your strong shoes and warm clothes for this walk in a beautiful area of the Green Mountains. You may go hiking or have a try of rock climbing. This is also a protection area for wild animals. You can find many kinds of animals living in this area.

Time: May 8—May 14   Tel: 64639818    Adult: $110     

Trip 2  Three days in the country

There are many beautiful gardens. Take your camera and enjoy the wonderful sight in Hunter Valley. It is a good place for fishing and horse riding. Bird lovers can also enjoy a great walk.

Time: May 20—May 22        Tel: 63986423   Adult: $50      Child: $25

Trip 3  Flashlight adventure

Put on your warm clothes, bring a torch, and come for a night walk along the Dungog Valley. It’s a trip full of adventure. A guide will lead the tour. Many of the plants you will see on this trip can only be seen at night.

Time: May 16—May 18     Tel: 63875629      Adult: $30       Not for children

Trip 4  Five days by the sea

Wear your sun hat and enjoy wonderful sunshine all the time from morning to evening. Our hotel is next to the sea. We have our own boats, too. You can swim in the sea or in the swimming pool. Every day our boat will take you to different places for swimming.

Time: May 23—May 27        Tel: 67538293     Adult: $80      Child: $40

小题1:If you want to enjoy the sunshine with your friends at the seaside, you can call _________.

A．67538293

B．63875629

C．64639818

D．63986423小题2:How much does Mr. Smith have to pay if he wants to stay in Hunter Valley with his wife and his five-year-old daughter?

A．$75.

B．$100.

C．$125.

D．$150.小题3:David can take part in _______ for ________ days from May 16 to May 18.

A．hiking in the mountains, 7

B．fishing in the country, 5

C．swimming in the sea, 3

D．walking at night with a torch, 3小题4:________clearly tells people that children can’t take part in this kind of trip.

A．Trip 1.

B．Trip 2.

C．Trip 3.

D．Trip 4.小题5:Which of the following is NOT mentioned in the four ads?

A．

B．

C．

D．
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策勒村抗俄斗争
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