题干

某溶液中可能含有H+、Na+、NH4+、Mg2+、Fe3+、Al3+、SO42﹣等离子,当向该溶液中加入某浓度的NaOH溶液时,发现生成沉淀的物质的量随NaOH溶液的体积变化如图所示.下列有关对该溶液的判断不正确的是(  )

A:该溶液中肯定含有的离子是H+、NH4+、Al3+、SO42﹣

B:肯定不含的阳离子是Mg2+、Fe3+

C:要确定该溶液是否含有Na+,必须做焰色反应实验,看焰色是否为黄色

D:该溶液中肯定含有的离子的物质的量之比为n(H+):n(NH4+):n(Al3+):n(SO42﹣)=2:3:1:4

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D

同类题1

从A-F中选择其中五个填入短文中相应空格处,其中一个选项是多余。

Giving directions in different places

    If you ask people of different countries "Could you tell me the way to the post office?", you will get different answers.

    In Japan, people use landmarks instead of street names. For example, the Japanese will say to travelers, "Go straight down to the corner. ____ The post office is across from the bus stop."

    In Kansas, America, there are no towns or buildings within miles. So instead of landmarks, people will tell you directions and distance. For example, people will say, "Go north two miles ____".

    People in Greece sometimes do not even try to give directions. They will often say, "Follow me." ____ Sometimes if a person doesn't know the answer to your question, he or she, like a New Yorker, might say, "Sorry, I have no idea." But in Yucatan, Mexico, no one answers "I don't know". ____ They usually give an answer, but often a wrong one. A visitor can often get lost in Yucatan!

____ You might not understand a person's words, but maybe you can understand his or her body language. He or she will usually point to the correct direction. Go on in that direction and you may find the post office!

A. Turn east, and then go another mile.

B. But one thing will help you everywhere.

C. People there think "I don't know." is not polite.

D. Turn left at a big hotel and go past a fruit market.

E. Then he or she will take you through the streets of the city to the post office.

F. Sorry, I don't know, I'm a stranger here.