问题 填空题

科学研究证实,物质从宏观上讲是由元素组成,从微观上讲是粒子构成的,例如铁是由铁原子构成的.请你在下列空格里,用“元素、原子、分子、离子”填空:

(1)水是由氧、氢两种______组成的; 

(2)保持氢气化学性质的最小粒子是氢______;

(3)化学变化中的最小粒子是______;

(4)体温计中的汞是由______构成的;

(5)用于人工降雨的干冰是由______构成的;

(6)用于配制生理盐水的氯化钠晶体是由______构成的.

答案

(1)水是由氧、氢两种元素组成的; 

(2)保持氢气化学性质的最小粒子是氢分子;

(3)化学变化中的最小粒子是原子;

(4)体温计中的汞是由汞原子构成的;

(5)用于人工降雨的干冰是由分子构成的;

(6)用于配制生理盐水的氯化钠晶体是由离子构成的.

故答为:

(1)元素;

(2)分子;

(3)原子;

(4)原子;

(5)分子;

(6)离子.

阅读理解

Once there lived an old man in a mountain village. He was a famous hunter. He often went hunting alone in the mountains. He was not afraid of any wild animals, not even a tiger.

One night, someone saw a tiger come into the village, and stole two sheep away. The next night the tiger came again. The villagers were frightened. They asked the old hunter to catch it so that they could have a safe life.

When the old man heard about the tiger, he thought hard. He wondered why the tiger came at night twice but only stole the sheep. The next night he walked outside the village. Suddenly he saw the tiger coming. He quickly threw himself on the ground. To his surprise, the tiger did not come at him, but went away. He followed it quietly and found it was running on two of its feet just like a man. Then everything was clear.

On the fourth day, when it got dark, the hunter took some animal skins with him and hid himself behind a big tree near the village. He was waiting for the "tiger". As soon as the "tiger" came near the tree, the old hunter jumped out, caught the "tiger" by the "leg" and said, "Don't be afraid. I do not mean to hurt you. You know who I am, don't you?"

The "tiger" said "Yes" and took off the tiger's skin.

"You are poor. But you mustn't steal anything from others. Here are some animal skins for you. You may sell them at the market. With the money, you can buy food and clothes for your family. Work harder and try to make a living. " With tears in his eyes, the poor man thanked the kind-hearted old hunter and walked home.

小题1:Where did the hunter live?

A.Outside a village.

B.On a farm.

C.In a village.

D.Near a village.小题2:How many times did the tiger come into the village?

A.Only once.

B.Twice.

C.Three times.

D.Four times.小题3:What did the old hunter do when he first saw the tiger?

A.He was frightened.

B.He threw himself on the ground.

C.He ran away.

D.He hid himself behind a tree.小题4:How did the old hunter know the tiger was a man?

A.The tiger came to the village only at night.

B.He saw the tiger run on its two feet.

C.The tiger only stole sheep.

D.The tiger could speak.小题5:Why did the old hunter take some animal skins with him when he was waiting for the "tiger" ?

A.To help the poor man.

B.To make himself well hidden.

C.To sell them at the market the next morning.

D.To buy food and clothes on his way home.

单项选择题