问题 选择题

在室温为0℃的房间里,把0℃的冰块放入0℃的水中,下列说法正确的是(  )

A.有些冰熔化成水使水增多

B.有些水凝固成冰使冰增多

C.冰和水的数量都没有变

D.冰的熔点为0℃

答案

晶体熔化的条件是:达到熔点,继续吸热.把0℃的冰放到0℃的水中,虽然达到了熔点,但是冰与水的温度都是0℃,由于没有温度差,所以不会有热传递现象发生,冰不能吸热,同样的水不会放热,所以冰不会熔化,水不能凝固,即冰和水的数量没有变化.

故选C.

填空题
阅读理解

Like most Oregonians, Stephanie McRae was used to driving in bad weather. Although rain still beat the window of her car, the worst of the day’s storm seemed to have passed as she drove her 11-year-old daughter, Maggie, home from a church at 8:30 p.m. Two little children sat into their car seats in back.

When crossing over Fawcett Creek (小河), McRae found the road just ahead had been washed away. The storm had turned Fawcett Creek into a 100-feet-wide river. Water began to go into the car and the four of them had to climb onto the car’s roof. The car was floating about and was being swept toward the Tillamook River only a few miles ahead. Suddenly it stopped when hitting a logjam (浮木阻塞).The water swept over them, rising higher and higher. Stephanie screamed into the rainy night, almost crying.

“Mom, I have to go and get help,” her 11-year-old daughter Maggie cried.

Stephanie realized if she went by herself, Maggie couldn’t hold on to the other two babies. But Maggie was still recovering from foot surgery. How could she manage? Finally she shouted, “I’m proud of you. Be careful!”

As Maggie McRae struggled to reach the shore, she was all wet. The sixth grader started running to the nearest house. Inside, the neighbors immediately called 911 and were told that firefighters were making their way toward another trapped car. Maggie joined the neighbors, and helped the rescue team point out where her mother was. The firefighters saved McRae and her children by using a 35-foot-long ladder.

When Stephanie reached land in safety, Maggie raced into her mother’s arms. “She hugged me for five minutes,” Maggie remembers. Maggie accepted an award for her heroism, but she’s happier to get back to her sports team and her family. 

小题1:What can we infer from the passage?

A.Without the logjam, McRae’s car would have been swept into the Tillamook River.

B.The rain became heavier when McRae drove home.

C.McRae’s car was the only vehicle that was blocked in the Fawcett Creek that night.

D.Most of the time the weather in Oregon is quite good.小题2:Stephanie McRae’s screaming on the car’s roof suggested that she felt ______.

A.surprised

B.helpless

C.disappointed

D.careless小题3:According to the passage, we can infer that Maggie ______.

A.was strong enough to hold the two children in the water

B.tried to swim to the bank in order to get help

C.stopped her sports activities due to her foot injury

D.rescued her family using a ladder小题4:Which of the following is in the correct order of events?

①Firefighters rescued McRae and her children from the river.

②Firefighters were sent to the broken road.

③The neighbors Maggie found called 911.

④The rescue team had got informed of the trouble at Fawcett Creek.

⑤Another trapped car was found in the river by the firefighters.

A.④②③⑤①

B.④③②①⑤

C.③④②①⑤

D.③④②⑤①小题5:What is the passage mainly about?

A.A heavy storm that damaged a road and killed lots of drivers.

B.A brave young girl who helped save her family from flood.

C.Firefighters who rescued a family late at night from flood.

D.Great neighbors who saved people swept away into a river.