同温同压下，等体积的两容器内分别充满由14N、13C、18O三种原子构成的一氧化氮和一氧化碳，下列说法正确的是
A．所含分子数和质量均不相同 B．含有相同的分子数和电子数
C．含有相同的质子数和中子数 D．含有相同数目的中子、原子和分子
答案：D
题目分析：根据阿伏加德罗定律及其推论可知，容器内气体的分子数是相等的。都是2个原子构成的，原子数相等。由于14N18O和13C18O的相对分子质量不相等，因此质量不等。质子数和电子数也是不相等的。而中子数相等，都是17，所以选项D正确，答案选D。
点评：该题是高考中的常见题型，属于中等难度的试题，重点考查学生对原子组成以及组成微粒之间数量关系的熟悉了解程度，有利于调动学生的学习兴趣，激发学生学习化学的积极性。另外该题还要利用好阿伏加德罗定律。
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| Most American families like to have a holiday in summer. Summer is a good season 1 holidays. It is very 2 during (在……期间) the months of July and August. Children do not go to school during these 3 months. Some 4 like to stay at home during the holiday. They work in the garden, visit friends, 5 books, or 6 TV. Many families 7 their lunch to a park or somewhere far 8 the city. They like to eat where there are many trees or there is a nice lake. If they live near the sea, they often go to the beach. They can fish, swim or enjoy the sun there. America is a large country. Many families travel by 9 or by train to see interesting places. They also travel by plane to a foreign country. Many big cities have many famous buildings, theatres, shops and other places 10 travellers (旅行者). | ||||
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