试题与答案

X、Y、Z、L、M五种元素的原子序数依次增大。X、Y、Z、L是组成蛋白质的基础元

题型:填空题

题目:

X、Y、Z、L、M五种元素的原子序数依次增大。X、Y、Z、L是组成蛋白质的基础元素,M是地壳中含量最高的金属元素。请回答下列问题:

⑴ L的元素符号为________ ;M在元素周期表中的位置为______________;五种元素的原子半径从大到小的顺序是____________________(用元素符号表示)。

⑵ Z、X两元素按原子数目比l∶3和2∶4构成分子A和B,A的电子式为_____________,B的结构式为____________。

⑶ 硒(se)是人体必需的微量元素,与L同一主族,Se原子比L原子多两个电子层,则Se的原子序数为_______,其最高价氧化物对应的水化物化学式为_______。该族2 ~ 5周期元素单质分别与H2反应生成l mol气态氢化物的反应热如下,表示生成1 mol硒化氢反应热的是__________(填字母代号)。

a.+99.7 mol·L-1 b.+29.7 mol·L-1 c.-20.6 mol·L-1 d.-241.8 kJ·mol-1

⑷ 用M单质作阳极,石墨作阴极,NaHCO3溶液作电解液进行电解,生成难溶物R,R受热分解生成化合物Q 。写出阳极生成R的电极反应式:_____________________________;由R生成Q的化学方程式:_________________________。

答案:

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题型:选择题

改革开放以来,全国人民代表大会及其常务委员会制定和通过了300多个法律和有关法律问题的决定,地方人大制定了400多项地方性法规。这说明[ ]

①全国人民代表大会是我国的最高立法机关

②人民代表大会制度是我国的根本政治制度

③我国的社会主义法律在不断健全和完善

④地方各级人民代表大会有制定基本法律的权力

A、②③④

B、①③④

C、①②③④

D、①③

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题型:阅读理解

Su Hua is studying at Cambridge, UK. She has bought a bicycle and is worried about security. Her friend, Kate, found this article and sent it to her.

Introduction

A lot of crime is against bicycles. About 150,000 bicycles are stolen every year and most are never found. You can prevent this happening by following a few careful steps.

Basic Security

Do not leave your bicycle in out-of-the-way places. Always lock your bicycle when you leave. Secure it to lampposts or trees. Take off smaller parts and take them with you, for example lights and saddles(车座).

Locks

Get a good lock. There are many different types in the shop. Buy one that has been tested against attack. Ask for a recommendation from a bike shop.

Marking

Security marking your bike can act as a deterrent(威慑) to a thief. It can also help the police find your bicycle. It should be clearly written and include your postcode and your house or flat number. This will provide a simple way to identify your bicycle.

Registration

There are a number of companies who will mark your bicycle for you. They will then put your registration number and personal details on their computer database. Then if your bicycle is found it will be easy to contact you.

Finally

Keep a record of the bicycle yourself: its make, model and registration number. You can even take a photograph of it, this will prove the bicycle belongs to you.

小题1:Which part of the article gives you information on how to lock up your bicycle when you leave it?

A.Locks

B.Marking

C.Registration

D.Basic Security小题2:The article advises you to keep a record of your bicycle ____________.

A.in the bike shop and your computer

B.in a police station and security company

C.in a security company and your university

D.by yourself and in a security company小题3:Which of the following statements is true?

A.More than 150,000 bicycles are stolen every year.

B.Leave your bicycle in out-of-the-way places.

C.Taking a photograph of your bike will help prove the bicycle belongs to you.

D.Always lock your bicycle even if you don’t leave.小题4:The main purpose of this article is _____________.

A.to tell you what to do if your bicycle is stolen

B.to suggest ways of keeping your bicycle safe

C.to give you advice on where to buy a good lock

D.to say why you shouldn’t keep your bicycle in a quiet place

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