题目内容

【题目】(1)油脂是________________的总称,天然油脂是________(填纯净物混合物)。

(2)为验证某液态天然油脂是否饱和,可采取的实验操作是________________

(3)10 g某天然油脂完全水解需要1.8 g氢氧化钠,1 kg该油脂进行催化加氢,需消耗12 g氢气才能进行完全。则1 mol该油脂中平均含有________mol碳碳双键。

【答案】(1)油 脂肪 混合物

(2)取少量液态天然油脂于试管中,向其中滴加1~2滴溴水,若溴水褪色,则证明该油脂是不饱和的,若溴水不褪色,则证明该油脂是饱和的(其他合理答案也可)

(3)4

【解析】(1)油脂是油和脂肪的总称,属于混合物。

(2)不饱和油脂能与溴发生加成反应,使溴水褪色。

(3)1 mol油脂与3 mol NaOH发生水解,1.8 g氢氧化钠为0.045 mol,说明10 g天然油脂为0.015 mol,则1 000 g油脂为1.5 mol,需要12 g(6 mol)的氢气完全加成,根据1 mol碳碳双键加成需要1 mol H2,则1 mol该油脂含有4 mol的碳碳双键。

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【题目】

Does Fame Drive You Crazy?

Although being famous might sound like a dream come true, todays star, feeling like zoo animals, face pressures that few of us can imagine. They are at the center of much of the worlds attention. Paparazzi (狗仔队) camp outside their homes, cameras ready. Tabloids (小报) publish thrilling stories about their personal lives. Just imagine not being able to do anything without being photographed or interrupted for a signature.

According to psychologist Christina Villareal, celebrities famous people worry constantly about their public appearance. Eventually, they start to lose track of who they really are, seeing themselves the way their fans imagine them, not as the people they were before everyone knew their names. Over time, Villareal says, they feel separated and alone.

The phenomenon of tracking celebrities has been around for ages. In the 4th century B.C., painters followed Alexander the Great into battle, hoping to picture his victories for his admirers. When Charles Dickens visited America in the 19th century, his sold-out readings attracted thousands of fans, leading him to complain (抱怨) about his lack of privacy. Tabloids of the 1920s and 1930s ran articles about film-stars in much the same way that modern tabloids and websites do.

Being a public figure today, however, is a lot more difficult than it used to be. Superstars cannot move about without worrying about photographers with modern cameras. When they say something silly or do something ridiculous, there is always the Internet to spread the news in minutes and keep their story alive forever.

If fame is so troublesome, why arent all celebrities running away from it? The answer is there are still ways to deal with it. Some stars stay calm by surrounding themselves with trusted friends and family or by escaping to remote places away from big cities. They focus not on how famous they are but on what they love to do or whatever made them famous in the first place.

Sometimes a few celebrities can get a little justice. Still, even stars who enjoy full justice often complain about how hard their lives are. They are tired of being famous already.

【1】 It can be learned from the passage that stars today________.

A. are often misunderstood by the public

B. can no longer have their privacy protected

C. spend too much on their public appearance

D. care little about how they have come into fame

【2】 What is the main idea of Paragraph 3?

A. Great heroes of the past were generally admired.

B. The problem faced by celebrities has a long history.

C. Well-known actors are usually targets of tabloids.

D. Works of popular writers often have a lot of readers.

【3】 What makes it much harder to be a celebrity today?

A. Availability of modern media.

B. Inadequate social recognition.

C. Lack of favorable chances.

D. Huge population of fans.

【4】 What is the authors attitude toward modern celebrity?

A. Sincere.

B. Skeptical.

C. Disapproving.

D. Sympathetic.

【题目】完成句子

1. When __________________________?(arrive)

演讲者何时到?

2. We __________________now.(play)

我们正在打篮球。

3. They __________________in Guilin.(spend)

下个暑假他们要在桂林度过。

4. They ____________________ to discuss how to make the city a most livable city tomorrow.(leave)

明天他们将动身出席一个会议,来讨论如何使这座城市成为一座宜居城市。

5. They ________________ which leaves at 9:00 p. m. this evening.(take)

他们将乘坐今天晚上9点的火车。

6. Where ________________this weekend?(go)

这个周末他们要去哪里?

7. They ________________to put their gold in it.(dig)

他们在挖洞放金子。

8. We ______________when we are asked to practice singing.(about)

我们正要动身回家,就在这时被叫去练歌。

9. The Queen ______________next month.(visit)

下个月,女王将访问非洲。

10. I ________________after school.(play)

放学后我打算去弹钢琴。

11.We insisted that father____________________for the good of his own health.

们坚决要求父亲为他个人的健康而戒烟。

12. English is________________________well in a short time.

我们难以在短时间内学好英语

13. Maths is easy to learn____________________.

一旦你理解了规则数学就不难学了。

14. ________________________you may say, I wont believe you.

不管你说什么我都不会相信你。

15. We____________________when we were asked to practise singing.(about)

我们正要动身回家就在那时被叫去练歌。

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