[题目]在25℃时.某稀溶液中由水电离产生的c(OH-)＝10-10mol/L.下列有关该溶液的叙述正确的是( )A．该溶液一定呈酸性B．该溶液中的c(H+)可能等于10-5C．该溶液的pH可能为4.可能为10D．该溶液有可能呈中性题目和参考答案——青夏教育精英家教网—

题目内容

【题目】在25℃时，某稀溶液中由水电离产生的c(OH－)＝10－10mol/L。下列有关该溶液的叙述正确的是( )

A．该溶液一定呈酸性

B．该溶液中的c(H＋)可能等于10－5

C．该溶液的pH可能为4，可能为10

D．该溶液有可能呈中性

【答案】C

【解析】由水电离出来的c(OH－)＝10－10，故溶液中的c(H＋)水＝c(OH－)水＝1×10－10mol/L，若溶液中的c(OH－)＝10－10，则该溶液中的c(H＋)应等于10－4，则溶液的pH应为4，溶液呈酸性；若溶液中的c(H＋)＝10－10，则溶液的pH应为10，(该溶液中的c(OH－)应等于10－4)，溶液呈碱性；溶液可能是呈酸性也可能是呈碱性，但溶液不可能是pH＝5的溶液，当然也不可能呈中性。

练习册系列答案

黄冈经典阅读系列答案

文言文课外阅读特训系列答案

轻松阅读训练系列答案

南大教辅初中英语任务型阅读与首字母填空系列答案

相关题目

【题目】书面表达

你校校报的英语专栏正在开展以“健康的生活方式”为主题的英语征文活动，你打算参加。请根据以下提示信息写一篇英语短文。

1. 营养均衡的膳食；

2. 经常参加体育锻炼；

3. 乐观的人生态度。

注意：

1.字数100左右（开头已给出，但不计入总词数）；

2.可适当增加细节，以使行文连贯。

All of us want to live a healthy life. The following are some useful tips._____________________________

____________________________________________________________________________________________

【题目】古有孔孟圣人,今有道德楷模徐立平、吴锦泉等。人们心目中的道德典范,总是带有不同时代的印记。道德总是随着时代的发展被赋予新的内涵。这说明

A.所有的道德楷模都是社会主义先进文化的集中代表

B.道德楷模的力量是社会和谐与人民幸福的决定因素

C.社会主义道德与传统美德是一脉相承而又与时俱进的

D.应不断继承和发扬具有悠久历史的中国古代传统道德

【题目】In this lecture,I can only give you a purely___view of how we can live life to the full and make some suggestions about the future

A.private

B.personal

C.unique

D.different

【题目】“孝”是儒家伦理思想的核心。然而，近年频频爆出的关于“扶不起”(面对摔倒的路人，不肯、不敢上前搀扶等现象)种种负面新闻。人们开始怀疑我们这个社会是否正遭遇“道德寒冬”。面对这一窘境，某市的做法是：大力宣传中华传统美德，加强舆论的正面引导作用；深入挖掘人们内心深处向善的因素，树立助人为乐的道德典范；制定《公民救助行为保护条例》，让那些主动去“扶”去“助”之人的合法权益得到保护，使“扶得起”变成人人欲为的德行，实现由“不扶”到“扶”的变化。

从“加强思想道德建设”的角度，结合材料说明该市是如果实现由“不扶”到“扶”的转变的。

【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】相同物质的量浓度的NaCN和NaClO相比，NaCN溶液的pH较大，则同温同体积同浓度的HCN和HClO说法正确的是( )

A．电离程度：HCN>HClO

B．pH：HClO>HCN

C．与NaOH溶液恰好完全反应时，消耗NaOH的物质的量：HClO>HCN

D．酸根离子浓度：c(CN－)<c(ClO－)

【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】A

阅读下面短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

People around the world are remembering Nelson Mandela, South Africa’s first black president. He died Thursday at the age of 95.

South African President Jacob Zuma said, ＂The nation has lost its greatest son, and our people have lost a father. ＂

Mandela had been in poor health for several years. He was repeatedly treated in hospital, most recently for a lung infection. He became infected with tuberculosis(肺结核) many years ago while in prison.

Nelson Mandela was the main leader in efforts to end white minority rule in South Africa. He spent 27 years in prison for his part in fighting apartheid(种族隔离)—the nation’s policy of discrimination(歧视)against blacks.

Many world leaders, past and present, are remembering Nelson Mandela.

Frederick W. de Klerk was South Africa’s last apartheid leader. He freed Mandela from prison in 1990. Later, the two men won the Nobel Peace Prize. Mr. de Klerk said people will remember Mandela for the importance he placed on reconciliation(和解) — being able to reach a settlement between conflicting sides. He said their relationship was, in his words, ＂often stormy＂, but he said they were＂always able to come together at critical(关键的)moments. ＂

In the United States, President Barack Obama called Mandela an influential, brave and profoundly good human being. Mr. Obama said Mandela will be remembered for leaving a free South Africa at peace. ＂I am one of the countless millions who drew inspiration from Nelson Mandela’s life. My very first political action — the first thing I ever did that involved an issue, or a policy, or politics — was a protest against apartheid. I would study his words and his writings. ＂

In London, British Prime Minister David Cameron called Mandela a true global hero. In his words, a great light has gone out in the world.

【1】What does the underlined word ＂stormy＂ in Para. 6 mean?

A. rainy B. fierce C. peaceful D. challenging

【2】 What can we learn from the passage?

A. Frederick W. de Klerk is still an enemy of Mandela.

B. President Barack Obama learned a lot from Nelson Mandela’s life.

C. Nelson Mandela fought for the independence of South Africa.

D. Jacob Zuma called Mandela a true global hero.

【3】The passage is most likely a part of _________.

A. an advertisement B. a travel booklet C. a biography D. a newspaper

试题分类