试题与答案

如图是描述向氯化镁和盐酸的混合溶液中加入一定量的氢氧化钠溶液过程中产生沉淀的图象

题型:问答题

题目:

如图是描述向氯化镁和盐酸的混合溶液中加入一定量的氢氧化钠溶液过程中产生沉淀的图象.针对化学小组同学的猜想,请根据要求回答下列问题.

【提出问题】随着氢氧化钠溶液的加入的质量的不同,所得溶液中含有的溶质的成分也不同吗?

【猜想与假设】

张南同学猜想:加入氢氧化钠溶液在0~25g之间时,溶质的成分是NaCl和HCl;

小南同学猜想:加入氢氧化钠溶液恰好至25g时,溶质的成分是NaCl和MgCl2

小岗同学猜想:溶液中溶质只有NaCl;

【解释与结论】请对张南同学的猜想做出评价(1)______;

【解释与结论】小南同学猜想的理由是(2)______;

【解释与结论】小岗同学猜想溶液中溶质只有NaCl,这时加入氢氧化钠溶液的质量是(3)______;

【解释与结论】若加入氢氧化钠溶液的质量大于75g时,所得溶液的溶质成分的化学式是(4)______;

【归纳与总结】对于化学小组同学在分析反应后溶液中溶质成分时,需要考虑的是(5)______.

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B解析:肾移植术后应该监测血压、尿量,如果病人尿量

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题型:阅读理解

阅读理解。

     Long long ago, a young man became a great archer (射手). He asked the king to declare him as the

greatest archer of the country. The king was going to do so when an old servant of the king said, "Wait,

sir. I know an old man who lives in the forest. He is a much greater archer. Let this young man go to him

and learn from him for at least three years."

     The man could not believe that there could be a greater archer than him,but he went and found the old

man and he was! For three years he learned from him. Then one day,when he thought he had learned

everything,the thought came to him: "If I kill this old man, then I will be the greatest archer." The old man

had gone to cut wood and he was coming back carrying wood on his shoulder. The young man hid behind

a tree, waiting to kill him. He shot an arrow.

     The old man took a small piece of wood and threw it.It struck (击中) the arrow and the arrow turned

back and hurt the young man very deeply. The old man came, took out the arrow and said,"I knew that some

day you were going to do this.That's why I have not taught you this secret.There is no need to kill me. My

teacher is still alive, and I'm nothing before him.You must be with him for at least thirty years. And he is very

old, so go fast! Find the old man!"

1. The underlined word "declare" in the 1st paragraph is closest in meaning to "______".

A. serve

B. tell

C. announce

D. choose

2. The young archer wanted to kill the old man in the forest because ______.

A. he had nothing more to learn from him

B. he could then become the greatest archer

C. the old man refused to teach him everything

D. the king's old servant ordered him to do so

3. The following pictures show what happened between the young archer and his teacher.

Which is the right order of the story?

A. 1→2→3→4

B. 4→3→2→1

C. 4→2→3→1

D. 4→2→1→3

4. What do you think would most probably happen next?

A. The young archer died soon after he got hurt.

B. The king declared the young man the greatest archer.

C. The young archer found the old man's teacher and killed him.

D. The young archer set off (动身) to look for the old man's teacher.

5. What can you learn from the story?

A. There's always someone better than you in this World.

B. You must never try to become better than your teacher.

C. The older a mall is,the better archer he usually becomes.

D. Always use a piece of wood to protect yourself from an arrow.

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