题干

2011年3月11日日本发生9级地震,福岛核电站发生核泄漏,主要放射性物质131  53I,下列有关131  53I叙述正确的是

A:131 53I是碘的一种同素异形体

B:131 53I是一种新发现的元素

C:131 53I核外电子数为131

D:131 53I核内的中子数与核外电子数之差为25

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D

同类题5

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    He was struggling (费劲) to tie his shoes. I was struggling with whether I should help him. I did, and he was thankful.

   “Thank you”, he said.

  “I'm glad I could help. I just thought it would be easier for me to reach.” I said.

    He was a disabled man, and had to look down most of the time. His arms and legs were twisted (扭曲的) terribly, and he couldn't do what the rest of us would consider easy tasks. He always managed to look up to see how you respond to his words, however. He had a big smile, making me feel comfortable.

    I was still on my knees by his wheelchair.

   “Nice shoes,” he said.

  “Thanks. No one ever complimented me on them before,” I said.

  “No one has the same view of the world as I do,” he replied.

  “Tell me about the world as you see it,” I said smiling.

  “Most people can see if someone is comfortable with them or not in their eyes. I see it in their feet,” he said. “If people keep moving their feet, I just let them go, because I know they're not patient with me. I don't want to make people uncomfortable.”

   “What about me?” I asked.

   “I could see your compassion (同情). And then you came down to my level. I was the one who was nervous,” he said. “I don’t normally have someone look me in the eye.”

   “They don't know what they are missing,” I told him.

   “My cold is nothing to brag about (自夸),” he said.

   “But that smile is so big.”

     Yes, and it's not only a big smile but an attitude.