试题与答案

下表给出几种氯化物的熔沸点: NaClMgCl2CaCl2SiCl4熔点(℃)8

题型:选择题

题目:

下表给出几种氯化物的熔沸点:

 NaClMgCl2CaCl2SiCl4
熔点(℃)801712782-68
沸点(℃)14651418160057
对此有下列说法与表中数据一致的说法正确的是:(     )

A.CaCl2晶体中的离子键比MgCl2晶体中的离子键弱;     B.SiCl4是分子晶体;

C.801℃时,NaCl可形成气态;                                         D.MgCl2水溶液不能导电。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B解析:[知识点] 数据库的一致性和完整性;实体完整性、域完整性、参照完整性[评析] 在关系模型中实体及实体间的联系都是用关系来描述的。这样就自然存在着关系与关系之间的引用。引用的时候,必须取...

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阅读下面的短文,根据短文后的要求答题(请注意问题后的字数要求)。

[1]Do you like chocolate? Most people do.Some like it in bars.Others just like big squares of it.

[2]Say you just got a box of chocolate.Which piece do you pick first? A study carried out by a professor in the University of Virginia showed that people's choices of chocolates show their personality.If you choose a round piece, you are a person who likes to party.If you select an oval shape, you are a person who strives.You like to make things and push yourself to be successful.Picking a square shape shows that this is an honest and truthful person you can depend on.

[3]What kind of chocolate do you pick? Maybe you like milk chocolate.This shows you have warm feelings about the past, while dark chocolate means something else—the person who chooses it looks forward to the future.What about white chocolate? Would you like to choose it?      , you may find it hard to make up your mind.Those who like chocolate with nuts are people who like to help others.

[4]Do you believe these ideas? Can chocolate tell all these things? It doesn't matter.There is one sure thing about eaters of chocolates - they eat it because they like it.

小题1:What is the main idea of the text? (no more than 6 words.)

                                                                        

小题2:Fill in the blank (Paragraph 3 Line 3) to complete the sentence(no more than 5 words)

                                                                       

小题3:What does the underlined word “this”(Paragraph 2 Line 4) refer to? (no more than 8 words)

                                                                       

小题4:What’s the writer’s attitude towards the information about chocolate in the text?(no more than 15 words)

                                                                       

小题5:According to the passage, what of chocolate can show your characteristics and qualities?(no more than 2 words)

                                                                       

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