问题 问答题

为了研究水的沸腾,小文观察了水在加热过程中温度随加热时间的变化情况,并记录了有关数据如下表:

(1)小明观察到同学们测水温的操作如图中所示四种,你认为正确的是(______)

(2)实验中水的沸点是______℃;继续给沸腾的水加热,水的温度______(选填“升高”、“不变”或“降低”).

(3)实验中水的沸点低于100℃,你认为可能是______造成的.(只需要写出一个可能原因)

答案

(1)温度计在使用时玻璃泡不能接触器壁和底部,要完全浸入在液体中,所以A、C、D不符合题意,只有B符合题意;

(2)由表格分析可知,5min后水的温度不再改变,所以水的沸点是98℃;

(3)因为水的沸点会随着气压的改变而改变,因沸点小于100℃,所以当地气压可能小于一个标准大气压;

故答案为:(1)B;

(2)98;不变;

(3)当地气压小于一个标准大气压.

阅读理解

You either have it, or you don’t—a sense of direction, that is. But why is that some people would find their way across the Sahara without a map, while others can lose themselves in the next street?

Scientists say we’re all born with a sense of direction, but it is not properly understood how it works. One theory(理论) is that people with a good sense of direction have simply worked harder at developing it. Research being carried out at Liverpool University supports this idea and suggests that if we don’t have it, we lose it.

“Children as young as seven have the ability to find their way around,” says Jim Martland, Research Director of this project. “However, if they are not allowed out alone or are taken everywhere by car, they never develop the skills.”

Jim Martland also emphasized(强调) that young people should be taught certain skills to improve their sense of direction. He makes the following suggestions:

If you are using a map, turn it to the way you are facing.

If you leave your bike in a strange place, put it near something like a big stone or a tree. Note landmarks on the route as you go away from your bike. When you return, go back along the same route.

The simple way of finding your direction is by using lines such as streets in a town, streams, or walls in the countryside to guide you. Count your steps so that you know how far you have gone and note any landmarks such as tower blocks or hills which can help you find out where you are.

Now you will never get lost again!

小题1:Scientists believe that            .

A.only some babies are born with a sense of direction

B.people never lose their sense of direction

C.people learn a sense of direction as they grow older

D.everybody has a sense of direction from birth小题2:What is true of seven-year-old children according to the passage?

A.They never have a sense of direction without a map.

B.They have a sense of direction and can find their way around.

C.They should never be allowed out alone if they lack a sense of direction.

D.They can develop a good sense of direction if they are driven around in a car.小题3:If you leave your bike in a strange place, you should             .

A.tie it to the tree in order to prevent it from being stolen

B.draw a map of the route to help remember where it is

C.take the different routes when you come back to it

D.remember something easily recognizable(可辨认的) on the route

单项选择题