题干

类比(比较)是研究物质性质的常用方法之一,可预测许多物质的性质。但类比是相对的,不能违背客观实际。下列各说法中,正确的是(    )

C:IVA族元素氢化物沸点顺序是:GeH4 > SiH4 > CH4;则VA族元素氢化物沸点顺序也是:AsH3 > PH3 > NH3

A:CH4是正四面体结构,SiH4也是正四面体结构

B:NaOH是强电解质,饱和溶液导电能力很强;Ca(OH)2也是强电解质,其饱和溶液导电能力也很强

D:CaCO3与稀硝酸反应生成CO2,CaSO3与稀硝酸反应生成SO2

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答案(点此获取答案解析)

A

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    There was my mother, standing in a fuzzy (毛绒绒的) pink bunny(兔子)costume. This can't be, 1 I thought to myself. Being ten was 2 enough.

    Our class was taking a trip to a convalescent home(疗养院) that day.I had 3 to stay at home pretending I'd caught some rare disease. My mother who's a(n) 4, sent me to school anyway.

    When we got there, I 5 wished for that 6. I'd fall to the ground and be 7the humiliation (耻笑) of anyone ever knowing that I 8every day after school there, dressed as a bunny.

    “Hi, Shelly!” The residents waved at me, “ Do you know them?” someone asked. “No! They 9 me for someone else. I'm Machille,” I responded. I didn't look up 10 I might make eye contact with them. Then, Mrs. Deist, our teacher, handed us tulips (郁金香) to give to the residents. I quickly went to the back of the 11. My mother just went along her way--- hopping(单足跳跃). Last year, we hopped together. 12, “I'm too old for that now”, I thought.

    I hid behind my class. “ Shelly, how about a game of Fish?” Lou asked. My class and teacher 13 and stared. “ Machille, do you know these people?” Mrs.Deist asked me.

“Um….yes!”  

    “Well you should 14 the way,” she said, smiling. So I stepped forward, handed a tulip to Rose, waved to Frank and gave Mr. Blusso a high-five.

    “My mother is in a convalescent home. I wish she could have someone like you to 15 her.” Mrs Deist said. My mother hopped over then. “This is my mom. Every day she looks after these special people who need nurses' care.” I stood straight as I 16 the information. My mother then explained a program where kids can 17 after school. The residents cheered at the18, and my class seemed excited, too.

    I realized how 19 it made me to make other people smile and feel good. I should never be 20 of that.