题干

元素周期表将已知元素科学有序地排列起来,便于我们研究它们的性质和用途,如图表示元素周期表的一部分,请回答下列问题:

(1)元素在周期表中的分布是有规律的,表中①②③所代表的三种元素中,属于非金属元素的是____ ;

(2)表中氮元素的化合价有多种,请写出化合价为+1价的氮的氧化物 ____  (用化学式表示);

(3)随着新元素的不断发现,元素周期表还将逐渐完善,最近,科学家用大量高速钙原子轰击铕原子,形成了117号元素的原子,该元素原子核中一定含有117个 ____ .

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②,N2O,质子

同类题4

       My now 7-year-old grandson, who lives 100 miles away, has kept my phone number in his mind since he was 4. Since then, he has been  1 me every night before he goes to bed to tell me about his day or just to say “Good night, Grandma.”
    He also often calls me at other times during the day just to  2  a happy or sad moment. Many times he's playing a basketball with one hand, or laughing with a friend about something that I  3quite understand, or crying about something he may or may not want to talk about while I'm on the other end of the phone. I just listen and empathize (同情) or laugh with him—just share his current (当前的)  4 . I always let him control the  5  , and the time he's on the phone with me. Many times I just listen to him play, or play games we've made up together that we can play over the  6 .   
      The only time I take control of the 7  is when he's ready to say goodbye at night. Often there are four special   8  I say to him every night. One night I thought maybe he was tired to hear those, so I didn't say them. He  9 called me back and told me that I forgot to say those sentences! I haven’t missed saying them since then!
      My friends all know that he is the most important for me.  10  I'm in church(教堂), or some place where I really can't take his call, I always politely excuse myself and talk to him, even if it's just for a minute to tell him I'll call him back in a few minutes.
He knows that he takes first place in my heart.