问题 选择题

下列物质中,导电性由大到小排列正确的是(    )

①500 mL 0.1 mol·L-1的氢氧化钠溶液 ②100 mL 0.1 mol·L-1的硫酸溶液 ③500 mL 0.1 mol·L-1的醋酸溶液 ④1 L 0.1 mol·L-1的酒精溶液

A.①②③④

B.④①③②

C.②①③④

D.①③②④

答案

   C

   电解质溶液的导电能力与离子浓度和离子电荷数有关,离子浓度越大,电荷越多,则导电能力越强。上述溶液浓度虽然都为0.1 mol·L-1,但离子浓度却不同,硫酸为二元强酸,完全电离离子浓度最大,醋酸是弱酸,部分电离存在电离平衡,离子浓度较小,酒精属非电解质不导电。

阅读理解

Before she appeared on the reality show (真人秀) Britain's Got Talent, Susan Boyle was just an ordinary middle­aged British woman.Now all this is going to change.

She lives in a house with her cat Pebbles in a tiny Scottish town.Because of learning difficulties, she doesn't have much education.But what she does have is a very good voice.As a kid, she sang in church and choirs and school plays.For a living, she sang at local pubs.

When she took the stage on April 10th her hair was untidy and her clothes seemed just_one_step_up_from rags.The audience laughed at her.

But then she opened her mouth.A few bars into the song and the laughing audience went silent.A beautiful voice was singing I Dreamed a Dream from the musical Les Miserables.Everyone was amazed.At the end of her song, the audience jumped to their feet and applauded wildly.

Almost overnight, Susan became a household name.She won fans and millions of admirers.Her online videos have drawn over 85.2 million hits.

Susan's story proved the truth of an old saying: “Never judge the book by its cover.” Susan may look ordinary, and doesn't have much dress sense, but she can certainly sing.

Susan's fans admire her courage, as much as they do her voice.She has experienced mockery and many disappointments, but her love for music has kept her going, which is worth anyone's respect.

小题1:According to the passage, Susan Boyle ________.

A.is a famous young actress

B.became famous after a show

C.used to be a good student

D.is good at dancing and has millions of admirers小题2:The underlined phrase “just one step up from” in the third paragraph probably means ________.

A.far from

B.close to

C.different from

D.the same as小题3:The audience jumped and applauded wildly because ________.

A.her hair was untidy and her clothes seemed just one step up from rags

B.she looked very funny

C.she sang so well that everyone was amazed

D.she made a foolish mistake in the end小题4:Susan Boyle has many fans now because of ________.

A.her beautiful face

B.her knowing how to dress

C.her good education

D.her beautiful voice and courage小题5:The passage is mainly about ________.

A.how to win fans

B.how to sing well

C.a woman's sudden success

D.a woman's simple life

单项选择题