题干

在恒温、恒容下,有反应2A(g)+2B(g)⇌C(g)+3D(g),现从两条途径分别建立平衡.途径Ⅰ:A,B的起始浓度均为2mol•L1;途径Ⅱ:C,D的起始浓度分别为2mol•L1和6mol•L1.以下叙述正确的是(   )

A:达到平衡时,途径Ⅰ的反应速率等于途径Ⅱ的反应速率

B:达到平衡时,途径Ⅰ所得混合气体的压强等于途径Ⅱ所得混合气体的压强

C:两途径最终达到平衡时,体系内各组分的百分含量相同

D:两途径最终达到平衡时,体系内各组分的百分含量不相同

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答案(点此获取答案解析)

C

同类题3

信息归纳: 请阅读下面这篇文章,根据所提供的信息,完成信息卡。

    One day, Howard Kelly, a poor boy who was selling goods from door to door in order to pay his way through school, found he had only one coin left, and he was hungry.

    He decided he would ask for a meal at the next house. However, he became very nervous when a lovely young woman opened the door. Instead of a meal he asked for a drink of water.

    Young woman thought he looked hungry so she brought him a large glass of milk. He drank it slowly, and then asked, “How much do I owe(欠) you?”

     “You don't owe me anything,” she replied, “We never accept payment for a kindness.” He said, “Then I thank you from my heart.”

    Years later that young woman became very ill and was finally sent to the big city, where they called in specialists (专家)to study her rare disease. Dr. Howard Kelly was called in for the consultation (咨询). When he heard the name of the town she came from, he went to her room. He recognized her at once. He decided to do his best to save her life.

    After a long struggle, the battle was won. The woman thought it would take the rest of her life to pay for the final bill. But when she saw the bill, she read these words: “Paid in full with one glass of milk” (Signed by Dr. Howard Kelly).

Information Card

The reason why the poor boy was selling goods

____

Howard Kelly's feeling when a lovely lady opened the door

____

The thing that the young woman brought him

____

The specialist who saved the woman

____

The final bill

____

同类题5

        Millions of people all over the world use the word OK. In fact, some people say the word is used more often than any other word in the world. OK means all right or acceptable. It expresses agreement or approval.

        ____ Some people say it came from the Native American Indian tribe known as the Choctaw(乔克托语). The Choctaw word “okeh” means the same as the American word “okay”. Experts say early explorers in the American West spoke the Choctaw language in the nineteenth century.

        But many people doubt this. Language expert Allen Walker Read wrote about the word “OK” in reports published in the 1960s. He said the word began being used in the 1830s. ____ Some foreign­born people wrote “all correct” as “o­l­l­k­o­r­r­e­c­t”, and used the letters OK. Other people say a railroad worker named Obadiah Kelly invented the word long ago. They say he put the first letters of his name—O and K—on each object people gave him to send on the train.

        ____ The organization supported Martin Van Buren for president in 1840. They called their group the OK club. The letters were taken from the name of the town where Martin was born—Old Kinderhook, New York.

        Then there is the expression A­OK. It is a space­age expression. It was used in 1961 during the flight of astronaut Alan Shepard. He was the first American to be launched into space. His flight ended when his spacecraft landed in the ocean, as planned. Shepard reported, “Everything is A ­OK.” ____ One story says it was first used during the early days of the telephone to tell an operator that a message had been received.

        There are also funny ways to say okay. ____ These expressions were first used in the 1930s. Today, a character on the American television series The Simpsons says it another way. He says okely­doke.

A.Some people say okey­dokey or okey­doke.

B.Still others say a political organization invented the word.

C.Therefore, it has become popular in that area from then on.

D.But many experts don't agree on what the expression means.

E.Still, language experts do not agree about where the word came from.

F.It was a short way of writing a different spelling of the word “all correct”.

G.However, some experts say the expression did not begin with the space age.