题干

下列图象能正确反映其对应的实验操作的是(  )

A:常温下向pH=10的NaOH溶液中不断加入水稀释

B:向等质量的Mg和MgO中分别加入足量等浓度的稀硫酸

C:向一定量的AgNO3和Cu(NO32的混合溶液中不断加入铁粉

D:向一定量的部分变质的氢氧化钠溶液中滴加足量的稀盐酸

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答案(点此获取答案解析)

B,C

同类题4

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    In the middle of a beautiful day, I was feeling lost, as if the world was crashing on me. didn't know which way to go, except to head out to the countryside. I went to the spot where I used to take my kids-when I still had kids. Now they had  1and were leaving.

I was sitting alone in my car when I saw a man in his seventies, whose problem appeared bigger than mine. He stood near the edge of the road,2a kite spindle(风筝线锭) in his hands. Apparently, lost in thought, he stared skyward. I 3my neck to see how successful he had been in 4 the clouds. Following his string with my eyes, I almost lost5 of the other end. Finally, the kite rested on what seemed to be the highest branch of the 6tree in the park.  Obviously,  that was his grandson's kite!  The kite was a replica (复制品) of a beautiful bald eagle, and its wings spread 70pen. Grandpa had only one 8to his problem: cut the string.

"You wanted it to fly as high as it could. Bill. didn't you?" "Yes, Grandpa,9 wanted to keep it forever. " "There just comes a time when the only thing you can do is to cut the string and let it go. Perhaps by doing that, when it flies very high like real eagles do, it will come back to us. " Grandpa said.

    I 10 how the old man cut the string to let fly the kite. As the two walked away, looked to the 11. There I saw my answer, too. Today I have to cut the final strings that kept my two boys 12my reach. Though I want to keep them forever, I have taught them to fly like an eagle. Maybe by doing this, when it's time to soar like real eagles do. one day they would come back to me.

同类题5

 One cold winter night in Shanghai, I was walking home at one in the morning after long tiring work. I was having trouble with my job in the bank. As I walked, I thought seriously about giving up living there. City life had become too much for me.

 As I walked down empty streets, I felt very small and cold. I began running, both to keep warm and to keep away any possible danger. Very few people were still out except a few sad-looking homeless people under blankets(毛毯).

 Suddenly, I heard a sound behind me. I turned quickly, all I saw was a shining streetlight. Still, the noise had made me nervous, so I started to run faster. When I reached home, I realized what the noise had been. It had been my wallet falling to the sidewalk.

 Now I wasn't cold or tired anymore. I ran back to where I'd heard the noise. Although I searched carefully for fifteen minutes, my wallet was nowhere to be found.

 Just as I was about to give up the search, I heard the garbage truck(垃圾车)come to me. When a voice called from the inside, “Alisa Chen?” I thought I was dreaming. How could this man know my name? The door opened, and out jumped a small red-haired man “Is this what you’re looking for?”he asked, holding up a small square shape.

 It was nearly 3 a. m. by the time I got into bed. But I had got my wallet back. I also had got back some enjoyment of city life. I realized that the city couldn't be a bad place as long as people were willing to help each other.