题干

短周期元素X、Y、Z、W在元素周期表中的相对位置如表所示,W原子的质子数是其最外层电子数的三倍.下列说法不正确的是(   )

A:元素Y有同素异形体

B:最高价氧化物对应水化物的酸性:X>Z

C:简单气态氢化物的热稳定性:Y>Z

D:原于半径:W>Z>Y>X

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D

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     Many of us feel uneasy when someone stands too close to us, talks to us too loudly or makes eye contact(接触) with us for too long. But have you ever wondered why those things make you uncomfortable?
      It's all about personal peace, which means not only an imaginary space around the body, but also the space around all the senses. People feel that their space is being violated(侵犯) when they meet with an unwelcome sound, smell or look. This is probably why a man on a crowded bus shouting into his mobile phone or a woman next to you putting on strong perfume(香水) makes you feel angry.

    Whether people have had a stronger wish to protect their personal space in recent times is hard to say. Yet studies of airlines show that people have a strong desire to have space to themselves. In a survey by Trip Advisor, a travel website, people said that if they had to pay more for some extra service, they would rather have larger seats than extra food.

    Although people may need their personal space, some hardly realize it. For example, people on a bus who hold newspapers in front of their faces to read in fact keep a distance from strangers.

    Go and watch a library table. You will notice that one of the corner seats will usually be taken first, because they are the farthest way. What if someone sits opposite to you? Maybe you will pile up books as if to make a wall.

    Preference for personal space is different from culture to culture. Scientists have found that Americans generally prefer more personal space than people from other cultures. In Latin cultures, however, people are more comfortable standing close to each other.