题干

下列关于晶体的说法中,不正确的是(   )

①共价键可决定分子晶体的熔、沸点【

②含有金属阳离子的晶体一定是离子晶体

③晶体中原子呈周期性有序排列,有自范性;而非晶体中原子排列相对无序,无自范性  

④MgO的晶格能远比NaCl大,这是因为前者离子所带的电荷数多,离子半径小

⑤晶胞是晶体结构的基本单元,晶体内部的微粒按一定规律作周期性重复排列

⑥干冰晶体中,一个CO2分子周围有12个CO2分子紧邻;CsCl和NaCl晶体中阴、阳离子的配位数都为6

⑦晶体尽可能采取紧密堆积方式,以使其变得比较稳定.

A:①②⑥

B:②③④

C:④⑤⑥

D:②③⑦

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A

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    It's generally believed that people act the way they do because of their personalities and attitudes. They recycle their garbage because they care about the environment. They pay $5 for a caramel brulee latte because they like expensive coffee drinks.

    It's undeniable that behavior comes from our inner dispositions(性情), but in many instances we also draw inferences about who we are, as suggested by the social psychologist Daryl Bern, by observing our own behavior. We can be strangers to ourselves. If we knew our own minds, why should we need to guess what our preferences are from our behavior? If our minds were an open book, we would know exactly how much we care about the environment or like lattes. Actually, we often need to look to our behavior to figure out who we are.

    Moreover, we don't just use our behavior to learn about our particular types of character — we infer characters that weren't there before. Our behavior is often shaped by little pressures around us, which we fail to recognize. Maybe we recycle because our wives and neighbors would disapprove if we didn't. Maybe we buy lattes in order to impress the people around us. We should not mistakenly believe that we always behave as a result of some inner disposition.

    Whatever pressures there can be or inferences one can make, people become what they do, though it may not be in compliance(符合) with their true desires. Therefore, we should all bear in mind Kurt Vonnegut's advice: “We are what we pretend to be, so we must be careful about what we pretend to be.”