题目内容

【题目】实验室制备硝基苯的主要步骤如下：①配制一定比例的浓硫酸与浓硝酸的混合酸，加入反应器中；②向室温下的混合酸中逐滴加入一定量的苯，充分振荡，混合均匀；③在50～60℃下发生反应，直至反应结束；④除去混合酸后，粗产品依次用蒸馏水和5%NaOH溶液洗涤，最后再用蒸馏水洗涤；⑤将用无水CaCl2干燥后的粗硝基苯进行蒸馏，得到纯净的硝基苯。

请填写下列空白：

(1)配制一定比例浓硫酸和浓硝酸混合酸时，操作的注意事项是__________________。

(2)步骤③中，为了使反应在50～60℃下进行，常用的方法是____________________。

(3)步骤④中洗涤、分离粗硝基苯应使用的仪器是___________________________。

(4)步骤④中粗产品用5%NaOH溶液洗涤的目的是____________________________。

(5)纯硝基苯是无色，密度比水______(填“大”或“小”)，具有________气味的油状液体。

【答案】(1)先将浓硝酸注入容器中，再慢慢注入浓硫酸，并及时搅拌和冷却

(2)将反应器放在50～60℃(或60℃)的水浴中加热

(3)分液漏斗

(4)除去粗产品中残留的酸

(5)大 苦杏仁

【解析】配制一定比例浓硫酸和浓硝酸混合酸的操作与浓硫酸的稀释操作相似。使反应在50～60℃下进行，常用的方法是水浴加热。硝基苯是不溶于水的液体，用分液的方法分离。粗产品用5%NaOH溶液洗涤的目的是除去未反应的酸。纯硝基苯的密度比水大，具有苦杏仁气味。

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C．给农作物补充适宜强度的人工光照

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【题目】A

Do you like visiting museums? Here are some of the best museums in the world.

The Rijksmuseum in Amsterdam is the largest and most famous museum for art and history in Holland. It has a large collection of paintings from the Dutch Golden Age, including works by Vermeer and Rembrandt. Until 2013, the museum is being completely restored, but the major great works are still on show.

The Museum of Modern Art in New York City is often considered the most influential museum of modern art in the world. It has the best collections of modern art works worldwide, including Monet’s Water Lilies, Picasso’s Les Demoiselles d’Avignon and Van Gogh’s Starry Night. Besides the artwork, one of the main attractions of the museum is the building itself.

Founded in 1764 by Catherine the Great, the Hermitage Museum in Saint Petersburg, Russia is a large museum of art and culture. It shows a collection of over 3 million items throughout the world. Being a popular tourist attraction, the Hermitage is truly one of the best museums in the world. It displays priceless works by Rembrandt, Da Vinci, Michelangelo, Reubens and more.

Built in 1753, the British Museum in London is a museum of human history and culture. Its collections, which include more than seven million objects, are among the largest in the world. Objects include the Rosetta Stone and the largest collection of mummies outside Egypt. It’s one of the top destinations in London.

Home to at least 120, 000 items of ancient Egyptian antiquities(古迹), the Egyptian Museum in Cairo is one of the world’s best museums. There are two main floors, the ground floor and the first floor. On the ground floor there is a collection of coins used by the ancient Egyptians. On the first floor there are artifacts from the final two dynasties of Ancient Egypt and also many artifacts taken from the Valley of the Kings.

【1】 If you want to see Van Gogh’s works in the most influential museum of modern art in the world, you should go to_____________.

A. London B. New York City

C. Amsterdam D. Saint Petersburg

【2】What do we know about the Hermitage Museum in Saint Petersburg, Russia?

A. It was built by Catherine the Great in the 17th century.

B. The items displayed in the museum are all worthless.

C. It displays a collection of over 3 million items from Russia.

D. Works of Da Vinci and Reubens can be seen there.

【3】 We learn that the Egyptian Museum in Cairo_____________.

A. is much larger than the others mentioned

B. has more items than the others mentioned

C. is one of the top destinations in the world

D. mainly displays ancient Egyptian antiquities

【4】 What’s the writer’s purpose in writing the passage?

A. To show that he or she really likes visiting museums.

B. To explain how the museums above were built.

C. To introduce some of the best musems in the world.

D. To encourage us to learn something about visiting museums.

【题目】金属镍有广泛的用途。粗镍中含有少量Fe、Zn、Cu、Pt等杂质，可用电解法制备高纯度的镍，下列叙述正确的是(已知：氧化性Fe2＋<Ni2＋<Cu2＋)( )

A．阳极发生还原反应，其电极反应式：Ni2＋＋2e－==Ni

B．电解过程中，阳极质量的减少与阴极质量的增加相等

C．电解后，溶液中存在的金属阳离子只有Fe2＋和Zn2＋

D．电解后，电解槽底部的阳极泥中只有Cu和Pt

【题目】某生物兴趣小组对学校草坪的某种雌雄同花的植物进行了遗传学研究，发现该种植物的花色有红色和白色两种。他们查阅资料后发现，该对性状受一对遗传因子控制。为了对该对性状做进一步研究，该小组随机取红花和白花植株各60株均分为三组进行杂交实验，结果如表所示：

组别

杂交方案

杂交结果

A组

红花×红花

红花︰白花=14︰1

B组

红花×白花

红花︰白花=7︰1

C组

白花×白花

全为白花

（1）根据 组结果，可以判断 色为显性．

（2）试解释A组结果没有出现3︰1性状分离比的原因 ．

（3）B组亲本的红花中，纯合子与杂合子的比例为 ．

（4）要判断B组杂交结果中某红花植株是否为纯合子，最简单的方法是 ．

【题目】听一段材料，回答下面几个小题。

【1】Where is the foreign language section?

A. In Row 3. B. In Row 5. C. In Row 7.

【2】What does the man decide to borrow?

A. Novels. B. Biographies. C. Magazines.

【题目】写出具有下列电子排布的微粒的核电荷数、元素符号,以及在周期表中的位置。

(1)A原子:1s22s22p5 、 ;第 周期第 族。

(2)B-:1s22s22p63s23p6 、 ;第 周期第 族。

(3)C原子:[He]2s22p3 、 ;第 周期第 族。

(4)外围电子排布为3d54s2的原子: 、 ;第 周期第 族。

【题目】完成句子

1. 这本书将明天给你。

The book ________________________________to you tomorrow.

2. 今晚将不会修理这些机器。

The machines are not ________________________________tonight.

3. 我们什么时候开会很快就会决定。

When we shall have the meeting ________________________________.

4. 如果天气允许，工作会按时完成。

If the weather permits, the work ________________________________on time.

5. 如果给我更多时间，这个题目就会算出来了。

If more time is given to me, the problem ________________________________.

【题目】听一段材料，回答下面几个小题。

【1】What kind of flowers does the man order?

A. Red roses.

B. White roses.

C. Yellow roses.

【2】How much will he pay?

A. $32.

B. $35.

C. $38.

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