题目内容

【题目】有三种物质AC2、B2C2、AD4,元素A的最高正价和负价绝对值相等;元素B的单质能在C的气态单质中剧烈燃烧,火焰呈黄色,并生成淡黄色固体B2C2;元素D的负一价阴离子的电子层结构与氩原子的相同,则:

(1)A、B、C、D的元素名称分别为 、 、 、 。

(2)AD4分子中含有的共价键类型为 (填“σ键”或“π键”)。

(3)D的负一价阴离子的电子排布式为 ,B2C2的电子式为 ,属 (填“离子化合物”或“共价化合物”)。

【答案】(1)碳 钠 氧 氯 (2)σ键

(3)1s22s22p63s23p6 Na+]2-Na+ 离子化合物

【解析】根据元素A的最高正价和负价绝对值相等,元素A是碳,根据淡黄色固体B2C2和火焰呈黄色,可知元素B是钠,元素C是氧,元素D的负一价阴离子的电子层结构与氩原子的相同,元素D是氯。

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【题目】B

Childhood bullying has long been considered to have a cruel and unnecessary effect on too many youngsters’ childhoods. But the consequences of it can be felt into adulthood when it comes to mental health, a new study has found.

Persistent bullying when young is also linked to relationships breaking down and low employment, they said.

Scientists have discovered it has a strong link to mental health service use throughout a person’s life. The study, by the London School of Economics and Political Science (LSE)King’s College London, tracked more than 9,000 people for about 40 years.

It found more boys than girls used mental health service in childhood and adolescence. On the contrary, more women than men were found to use it in adulthood.

Lead researcher Dr Sara Evans-Lacko said the impact of childhood bullying was most notable at an early age. But the associate professor from LSE’s personal social services research unit said it could still be significant at 50.

“Individuals who were frequently bullied during childhood were more than twice as likely to use mental health services during childhood or adolescence,” she said. “Even at the age of 50, they were still 30 percent more likely to use mental health services compared to those who were not bullied. Half the adult population with a psychotic(精神病的)disorder already showed signs of poor mental health by the age of 15.”

If unnoticed or untreated, the early onset (发病)of mental health problems could be the starting point of persistent disorders like depression and anxiety, self-harm and psychotic disorders, she said.

Early intervention to prevent childhood bullying would both help to stop distress and save money in healthcare over the course of a person’s life.

Dr Evans-Lacko said:“Anti-bullying initiatives(举措)are relatively inexpensive, estimated at ￡15.50 per pupil per year, and offer good value for money. Given the current tremendous stress on the health system, policies and practices to prevent bullying should be a high priority.”

【1】According to Dr. Evans-Lacko, .

A. childhood bullying has crueller effects on women than men

B. childhood bullying’s effects can only be felt in adulthood when it comes to mental health

C. the mental health services are too expensive for ordinary people

D. People should pay more attention to anti-bullying measures

【2】What does the underlined word mean?

A. Important. B. Lasting. C. Obvious. D. Immediate.

【3】People tend to use the mental health services when .

A .they are bullied more than twice in their childhood

B. they are bullied frequently during childhood

C. they have reached the age of 50 without being bullied

D. they are 15 with poor mental health

【4】Where does the text most probably come from?

A. Reader’s Digest. B. Psychological Medicine.

C. The Times. D. National Geographic.

【题目】B

If you are interested in studying at an American university, you have to take the Test of English as a Foreign Language. The test is widely known as the TOEFL. It is the most widely used language exam for American universities.

There are two major kinds of the TOEFL test. The first is the IBT，or Internet based Test. It is offered in most of the world and accepted by nearly every university and scholarship program in the United States. The other kind of the test is called the Paperbased Test or PBT. The PBT is less costly to take and does not require use of the Internet.

But how to get started with TOEFL? Here are some tips.

1. Plan ahead — It takes a long time to improve your TOEFL score. Do not expect a big lift in your test results after two weeks. You will have to spend a lot of time and energy.

2. Master the basics first — You should have to be good at basic English before you take the test. If you score below 500 on the PBT or 70 on the IBT, study for a few months and come back to the TOEFL later.

3. Get a study guide — It is easy to find study guides for the IBT. Pearson, Barron’s, ETS, and Kaplan all produce quality materials, take a practice test once or twice a month. The best study guides will have explanations in the answer key.

4. Use outside resources — Remember, you are learning a language, nota test. You can improve your TOEFL score by making English part of your daily life. Some simple ways are listening to English speakers, watching movies and reading newspapers. Some others are reading English textbooks, sending and reading text messages in English, and writing online in English.

The best way to do well on the TOEFL is to know English well. The real goal of the test is to measure how well a student can communicate in Englishspeaking classroom.

If you want to know more, please click here.

【1】 If you want to study in an America university, you have to ____________.

A. be very rich and work hard

B. be well prepared to take the TOEFL test

C. ask an English teacher to help you

D. prepare for a month before taking the TOEFL test

【2】From the passage we can learn that ____________.

A. the IBT is more expensive to take and requires use of the Internet

B. Pearson is a person who teaches quality materials

C. if you score 500 on the PBT, you can pass the TOEFL test

D. if you are good at reading, you can pass the TOEFL test

【3】 The real purpose of the TOEFL is to ______________, according to the passage.

A. get more foreign students to study in American universities

B. let foreign students know more about American universities

C. measure one's communicating ability in English

D. improve foreign students' skills of taking tests

【4】Where does the passage most probably come from?

A. A website. B. A lesson.

C. A science book. D. A novel.

【题目】

用方框印所给短语的适当形式填空。

consist of on stage apply for develop an interest in

give up at the age of take part in make friends with

【1】 This is the medical team five doctors and four nurses.

【2】 The doctor Persuaded him to smoking.

【3】 I’d’ like to whoever is outgoing and ready to help others.

【4】He painting when he was still a boy.

【5】 I always feel nervous before I go .

【6】 I still remember being taken to Beijing for the first time when I was ______ five.

【7】 She would sooner resign than such dishonest business s deals.

【8】 Don’t that job; you’re in danger of overreaching yourself.

【题目】回答下列问题：

(1)从鸡蛋白的溶液中提取蛋白质的方法有________和________。

(2)鸡蛋腐烂时，常闻到有刺激性气味的气体，该气体主要是________，说明蛋白质中含有________元素。

(3)误食重金属盐会中毒，这是因为_________________。

(4)浓硝酸溅到皮肤上，使皮肤呈现________色，这是由于浓硝酸和蛋白质发生了________反应的缘故。

(5)鉴定一种织物的成分是真丝还是人造丝，可各取一小块进行________，这是因为______________________。

【题目】在山羊遗传实验中,一黑色山羊与白色山羊杂交（白色与黑色由两对遗传因子控制且独立遗传）,子一代均为黑色。子一代个体间随机交配产生子二代个体中黑色∶浅黄色∶白色=12∶3∶1,则黑色个体和浅黄色个体中杂合子的比例分别为 （ ）

A．1/6、2/3 B．1/8、1/3

C．5/6、2/3 D．5/8、2/3

【题目】根据短文内容，从短文后的选项中选出能填入空白处得最佳选项。选项中有两项是多余选项。请将选项写到答题纸上。

It is said that there are about 40,000 different kinds of jobs in the world. 【1】“Finding a job ”is not the same as “choosing a job”. Many young people end up in a job which they are not suitable for. 【2】 Here are a few steps to help you think about jobs which you might enjoy doing after school or university.

First, it is important to realize what kind of person you are, which special qualities make you different from everyone else and what you are interested in . 【3】If you like art and enjoy looking at pictures, this is an interest. But if you can draw a horse that looks like a horse instead of a big dog, that is a skill.

Then ask yourself this question: in the following three areas----skills with people, skills with information and skills with things-----which are your best skills?

After examining your skills, the next step is research. To find out as many different kinds of jobs as possible, go to the library and read books, magazines and newspapers. 【4】

Finally, trust your own ideas and your own thinking! 【5】

A．It is your own life, so find something that you enjoy doing.

B．Choosing the right one itself is a difficult job.

C．We must know what our ideal jobs are.

D．There is a difference between an interest and a skill

E. Ask your friends about the work they do.

F. “Chance” may play a more important part than “decision”.

G. Your parents may also give you some useful advice.

【题目】甲状腺功能亢进症简称“甲亢”。现分别向正常人和甲亢病人静脉注射一定剂量的促甲状腺激素释放激素(TRH)，并于注射前和注射后连续取血测定血清中促甲状腺激素(TSH)的浓度，请回答下列相关问题：

（1）通常采取抽取血样方法来检测内分泌系统的疾病，是利用激素调节具有______________的特点。注射TRH后，与正常人相比，甲亢病人的血液中TSH浓度无明显变化的原因是：甲亢病人体内高浓度的甲状腺激素对垂体产生_________________。

（2）临床上80%以上甲亢是由Graves病引起的， Graves病患者体内存在TSH受体的抗体，所以Graves病属于____________病。

（3）甲状腺功能减退症简称“甲减”。甲减患者体内甲状腺激素合成和分泌减少的原因可能有_____________________________________（填器官，有三种)功能下降。若给某甲减病人注射TRH，结果血清中TSH无明显变化，表明病变的器官可能是__________。

【题目】听一段材料，回答下面几个小题。

【1】What's wrong with the lady passenger?

A. She is having a heart attack.

B. She is hurt in an accident.

C. She is having a baby.

【2】What's the nearest landmark to their location?

A. The Washington Tunnel.

B. The Lincoln Highway.

C. McDonald's.

【3】What can the man do for his passenger?

A. Help her breathe easily.

B. Keep her calm and warm.

C. Put something soft under her head.

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