问题 选择题

下列各组粒子中,每一粒子所含的质子数、电子数都是10的是(  )

A.He、Ne、Ar

B.Na+、Mg2+、Al3+

C.Ca、Mg、Al

D.Ne、H2O、NH3

答案

A、He、Ne、Ar是不同元素的原子,所以其质子数一定不同,故错误;

B、Na+、Mg2+、Al3+是三种不同元素的离子,所以其质子数一定不同,故错误;

C、Ca、Mg、Al是不同元素的原子,所以其质子数一定不同,故错误;

D、Ne原子的质子数是10其电子数也是10;H2O该分子的质子数为1×2+8=10,由于分子不带电所以其电子总数也是10;NH3该分子的质子数为7+1×3=10,由于分子不带电所以其电子总数也是10;故正确;

故选D

阅读理解
阅读理解。
     A man was walking along the street when he saw a woman carrying a large box. It was half in and half
out of her car. So the man went up and said, "The box looks very heavy. Let me give you a hand."
     "That's very kind of you," the woman said, "I'm having a lot of trouble with it. Maybe it stuck (卡住)
in the car door."
     "Together we'll soon move it," the man said. "I'll get in and take the other end." And he got in the car.
     "Right," the man said. "I'm ready," and he began to push the box hard.
      For several minutes, the man and the woman tried to move the box. Soon they felt very tired. 
     They rested for a moment. Then the woman said, "Let's try again. One, two, three!" They went on
moving the box.
     At last, when they were exhausted, the man said, "I'm sorry, but I don't think there's any way to get it
out of your car."
     "Get it out?" the woman cried. "I'm trying to get it in! You know?"
1. Where did this story happen?
[ ]
A. At a bank.
B. In a shop.
C. In the street.
D. In the woman's car.
2. Who got in the car to move the box?
[ ]
A. The woman.
B. The man.
C. Both of them.
D. Neither of them.
3. The underlined word "exhausted" means "______" in Chinese.
[ ]
A. 精疲力竭的
B. 激动的
C. 充满希望的
D. 沮丧的
4. Which of the following is TRUE about the story?
[ ]
A. The man stuck in the car door.
B. The woman asked the man for help.
C. The man refused to help the woman.
D. The woman tried to get the box into the car.
5. What do you think of the man?
[ ]
A. He is a helpful man.
B. He looks very strong.
C. He is funny and stupid.
D. He likes to play jokes on others.
选择题