试题与答案

在一个密闭容器内有a、b、c、d四种物质,在一定条件下充分反应,测得反应前后各物

题型:不定项选择题

题目:

在一个密闭容器内有a、b、c、d四种物质,在一定条件下充分反应,测得反应前后各物质的质量如下:下列说法正确的是

[ ]

A.该密闭容器中发生的化学变化属于分解反应

B.密闭容器中发生的化学变化属于化合反应

C.该反应中四种物质(参加反应或生成)的质量比为24∶15∶111∶84

D.反应后密闭容器中a的质量为22 g

答案:

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下面是错误答案,用来干扰机器的。

参考答案:E解析:考点:支气管哮喘的发病机制。哮喘的发病机制不完全清楚,可概括为免疫-炎症反应、神经机制和气道高反应性及其相互作用。而感染因素是COPD发作的重要因素之一。

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One day Trudy saw an advertisement in a magazine. It offered a packet of 100 mixed stamps for $10. Trudy wanted to start a stamp collection so she ordered the packet. One hundred mixed stamps seemed a good way to begin a collection. She sent a postal order to the stamp company with her order, and waited excitedly for the stamps arrived. Trudy checked the mail every day for four weeks but the stamps didn’t arrive. So Trudy decided to write to the company. “Dear Sir/Madam,” she wrote, “a month ago I sent you a postal order for $10 as payment for 100 mixed stamps. They haven’t arrived. Please send them by return of mail.” another month passed. The stamps still didn’t arrive and she didn’t receive any replay to her letter. She asked her father for advice. Her father said, “You must write a stronger letter. Make the stamp company worry that you will report them to the authorities.” “Dear Sir/Madam,” she wrote in her second letter. “I am writing to complain about your poor service. Two months ago I sent you a postal order for $10 as payment for 100 mixed stamps. I didn’t receive the stamps. A month ago I wrote to inform you of this. I still haven’t received the stamps, and you haven’t replied to my letter. If I do not receive the stamps within seven days. I shall report this matter to the authorities.” Two days later Trudy received the stamps in the mail.

小题1:Trudy ordered the stamps because _______.

A.it seemed a good way to start a stamp collection

B.she wanted to give them to her father

C.she need them to mail some letters

D.she thought they were cheap小题2:Trudy paid for the stamps with ________.

A.cash

B.a check

C.the credit card

D.a postal order小题3:Trudy checked the mail every day for ______.

A.4 months

B.a week

C.a month

D.for 3 weeks小题4:In her second letter Trudy complained about how _______.

A.expensive the stamps were

B.boring the stamps were

C.poor the company’s service was

D.slow the postal service was小题5:Trudy received the stamps ______ after she sent the second letter.

A.a week

B.a month

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