题干

在下列各组离子在一定条件下能够大量共存的是                      

A:无色溶液:Cu2、K、MnO4、SO42

B:能溶解Al2O3的溶液:Na、Ca2、HCO3、NO3

C:c(OH)=1×10-13mol·L-1的溶液:NH4、Al3、SO42、Cl

D:含0.1 mol·L-1 NO3的溶液:H、Fe2、Mg2、Br

上一题 下一题 0.0难度 选择题 更新时间:2018-11-26 04:02:54

答案(点此获取答案解析)

C

同类题2

阅读理解

D

    Life of Pi(少年派的奇幻河流)is to become the first 3D film to open the New York film festival. This year's New York film festival runs from September 28 to October 14.

    The director of this movie is Ang Lee, an American Chinese. The movie speaks of the relationship between humans and nature. Indian boy Priscine Patel is troubled by his first name. And his classmates laugh at him. So he decides to change his name to "Pi".

    Pi's father has a zoo and he decides to move to Canada. The family, together with all the zoo animals, sail across the pacific(太平洋). One day, a huge storm hits the ship. The next morning, Pi finds his family have sunk(沉没)with the ship. He is the only person still alive. He finds himself on a lifeboat with several animals, one of which is a tiger called Richard Parker. Soon, all the animals are killed by the tiger. And Pi is left alone with the tiger.

    As the tiger becomes hungry, Pi starts to fish to feed him. If not, he himself will become the food. The boy and the tiger develop an amazing relationship on the sea. Although he feels hopeless, Pi never gives up. After 227 days, the lifeboat finally lands on a beach in Mexico, but Richard Parker runs away into the forest. The ship company finds Pi and asks him what happened. Pi tells them about Richard Parker, but the company doesn't believe him. Pi then tells another story in which is no tiger.

    Is there really another story? If so, which one is true? Maybe you will have your answer after watching the Life of Pi.

同类题3

根据短文理解,选择正确答案。

    Andy never wanted to go to bed on time. His parents had explained to him how important it was to go to bed early and get a good rest. But Andy paid no attention to them, and they didn't know what to do until one weekend when they were visiting Andy's grandparents.

    Grandpa Peter heard all about it and said, "This sounds like a job for Tubby." So Andy's parents loaded the cat onto the car and returned home.

That night, at bedtime, the same problem happened. Andy didn't want to go to bed, and even though his parents waited a while to see if Tubby would solve the problem, nothing happened.

    Hours later, Andy finally decided to go to bed. But what a surprise when he entered his bedroom! Tubby was in his bed, totally sprawling out, pot-belly in the air, and snoring like an express train.

    Andy tried to move the cat, but there was no way of moving him an inch. That night he hardly slept, lying on one tiny corner of his bed.

    The next day the same thing happened, even though Andy was much more tired from not having slept well. When the third day arrived, he had understood that if he wanted to sleep in his bed, he would have to get into it before Tubby did. That night, when his parents only started to mention the topic of bedtime, Andy rushed upstairs and dived into bed. His parents could not believe it. They knew nothing about Tubby in the bed, nor did they understand why Andy went to bed on time without complaint. They were so happy about this that they stayed up quite late, celebrating.