问题 填空题

元素周期律是学习和研究化学的重要工具。下图是周期表的部分信息:

 认真分析信息回答:

(1)地壳中含量最多的金属元素的符号是___________;

(2)表示的是(填名称)___________;

(3)由l、8、12号元素组成的化合物的化学式___________;

(4)上表中每一周期元素原子序数的变化规律是_____________________________________。

答案

(1)Al

(2)氯离子

(3)Mg(OH)2

(4)从左到右原子序数依次增大

阅读理解

A

Insomnia is the inability to fall asleep or sleep restfully. It is a problem to nearly everyone at some time .A person may be awake for an hour in the middle of the night and then , next morning, feel that he hardly sleep all night Normally, worry about not getting enough sleep is the worst aspect of most insomnia. If insomnia is recurrent, however, it is important to find its causes and try to correct them, with the help of a doctor if necessary.

Any of a large number of simple factors may take it difficult for someone to fall asleep or remain asleep. His matters may be too soft or too hard. If there are too many blankets on a hot night, he may be too warm; if the bedclothes are too light he may feel cold during the night. If it is not dark enough, or too noisy, this may cause difficulty in sleeping. Eating shortly before going to bed also be responsible for insomnia. Stimulating drinks, such as tea or coffee, can also keep people awake.

Inability to fall asleep is sometimes a symptom of emotional or mental disorders. Insomnia may also be caused by pain and, very rarely, it can be a symptom of a physical disease.

The cause of insomnia may be easy to correct. The sufferer should check the mattress, bedclothes and bedroom temperature, and make any necessary changes. An eye mask keeps out the night and ear-plugs shut out sound. He should relax for an hour or two before bedtime, perhaps by reading a book; watching TV, or taking a warm bath. If he wakes during the night he should try turning on the light and reading for a while. Taking warm milk and a biscuit or two may be helpful. Above all, he should try not to worry about sleeplessness when someone is tied enough he nearly always falls asleep.

If necessary, a doctor may prescribe tranquillizers or sleeping pills. Take only the dosage he prescribes; any more is dangerous.

1. According to the writer, insomnia is ______.

[ A ] a rare problem                 [ B ] a sign of illness

[ C ] a common complaint            [ D ] a modern disease

2. People who have difficulty sleeping should sleep in_____.

[ A ] a light room                   [ B ] a dark room

[ C ] a cold room                   [ D ] a warm room

3. Insomnia need’t be taken seriously because_______.

[ A ] people can catch on sleep during the day.

[ B ] many people sleep far too much.

[ C ]it can easily be cured by doctors.

[ D ]it is cured naturally by tiredness.

4. The main cure for insomnia is_____.

[ A ] not to read too much at night

[ B ]not to eat too much for supper

[ C ] not to watch too much television

[ D ] not to get too anxious about sleeping

问答题 简答题