试题与答案

一氧化氮与一氧化碳都是汽车尾气里的有害物质,它们能缓慢地起反应生成氮气和二氧化碳

题型:选择题

题目:

一氧化氮与一氧化碳都是汽车尾气里的有害物质,它们能缓慢地起反应生成氮气和二氧化碳.对此反应,下列叙述中正确的是(  )

A.使用催化剂能改变平衡常数

B.使用催化剂能改变反应速率

C.改变压强对反应速率没有影响

D.降低压强能加大反应速率

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

Some British and American people like to invite friends for a meal at home. You should not be upset(不安的)if your English friends don’t invite you home. It doesn’t mean they don’t like you. Dinner parties usually start between 7 and 8 p.m. and end at about 11. Ask your hosts(主人)what time you should arrive. It’s polite to bring flowers, chocolates or a bottle of wine as a gift. Usually the evening starts with drinks and snacks(小吃). If you want to be extra polite, say how much you like the room, or the pictures on the wall. But remember-it’s not polite to ask how much things cost. In many families, the husband sits at one of the table and the wife sits at the other end. They eat with their guests. You’ll probably start the meal with soup or something small, then you’ll have meat or fish with vegetables, and then dessert(甜点心), followed by coffee. It’s polite to finish everything on your plate and to take more if you want it. Did you enjoy the evening? Call your hosts the next day, or write them a short “thank you” letter. British and American people like to say “thank you, thank, thank you” all the time!

小题1:If your English friend doesn’t invite you to dinner at home, it means he or she ______.

A.doesn’t like you

B.likes you

C.can’t afford to do so

D.is too busy小题2:It’s impolite ______.

A.to ask about the price of a certain thing

B.to say “thank you” to hosts

C.take nothing with you when you are invited to dinner

D.to eat up everything on your plate小题3:The meal ends with _______ usually.

A.soup

B.coffee

C.meat or fish

D.dessert小题4:When you are invited to a dinner party, you’d better _______.

A.ask what time you should arrive

B.take your wife with you

C.drink as more as possible

D.eat more snacks as you can小题5:Which of the following is true?

A.The hosts like the people who sit closer to them.

B.The hosts like the people who ask them time, price, age, etc.

C.The husband and the wife usually sit together.

D.You can call your host the next day or write a letter of thanks after that

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题型:问答题

x气体可能由CH4、H2、CO中的一种或几种组成,某化学兴趣小组的同学利用如下装置进行实验验证该气体的组成.(碱石灰的主要成分为NaOH和CaO)

(1)写出CH4燃烧的化学反应方程式______.

(2)填写下列实验报告.

实验操作实验现象实验结论
打开分液漏斗上端玻璃塞和下端活塞,______若______X气体为H2
若______X气体为CO
(3)若x气体燃烧后有水和二氧化碳生成,则x气体的组成可能为______.

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