问题 填空题

根据下列粒子的结构示意图,我能回答下列问题:

⑴表示同种元素的粒子是__________________________________(填序号);

⑵在化学反应中容易得到电子的粒子是______________________(填序号)。

⑶随着“神舟六号”的发射成功,我国还将发射绕月探测卫星。其任务之一是寻找一种新能源——氦3, 氦3原子核是由一个中子和两个质子构成的,其原子核外电子数为      

答案

(1)AD (2)AC  (3)2 

题目分析:(1)粒子结构图:①圆圈内的数字:表示原子的质子数②+:表示原子核的电性③弧线:表示电子层④弧线上的数字:表示该电子层上的电子数,而元素是具有相同质子数(或核电荷数)的一类原子的总称。注意:元素是一类原子的总称;这类原子的质子数相同,因此:元素的种类由原子的质子数决定,质子数不同,元素种类不同。所以表示同种元素的粒子是A、D,因为质子数相等,

(2)元素最外层电子数与元素性质的关系:金属元素:最外层电子数<4 ,易失电子,非金属元素:最外层电子数≥4 ,易得电子,稀有气体元素:最外层电子数为8(He为2),不易得失电子,所以在化学反应中容易得到电子的粒子是A、C,因为它们的最外层电子数≥4 ,易得电子

(3)在原子中,核电荷数 = 质子数 = 核外电子数,氦3原子核是由一个中子和两个质子构成的,

其原子核外电子数为2

阅读理解

阅读短文,选择正确答案。

    Can plants eat people? Probably not, but there are many plants that eat meat. Some of them are big, and they

can eat small animals. One famous meat-eating plant is the Venus flytrap (捕蝇草).

    The Venus flytrap is a very strange plant. It grows in dry parts of the United States. Its leaves are like the

pages of a book. They can open and close very quickly. Inside the leaves, there are three small hairs. If a fly

touches one of the hairs, the leaf closes quickly. The fly cannot get out. In about half an hour, the leaf presses

the fly until it is dead. Then, the plant covers the fly. Slowly, the plant eats the fly.

    Why do plants do it? Most plants get what they need from the sun, the air and the ground. In some places,

the ground is very poor. It doesn't have all these important things, especially nitrogen (氮). Animal meat has a lot

of nitrogen, so some plants eat meat to get what they need. Let's hope that some of the bigger plants don't get

the same idea!

1. The Venus flytrap is a kind of             . [ ]

A. plant

B. animal

C. food

D. meat

2. The Venus flytrap grows in             . [ ]

A. most parts of the world

B. some parts of Africa

C. dry parts of the United States

D. wet parts of England

3. From the passage, we learn that             . [ ]

A. all plants can eat people

B. all plants can eat animals

C. some plants can eat people

D. some plants can eat animals

4. The underlined word "presses" probably means              in Chinese. [ ]

A. 挤压

B. 关上

C. 打开

D. 松开

5. Why do some plants eat animal meat? Because             . [ ]

A. plants are dangerous to animals

B. animals are dangerous to plants

C. plants want to get what they need from animal meat

D. Plants want to protect themselves against animals

单项选择题