题干

焰火“脚印”、“笑脸”、“五环”让北京奥运会开幕式更加辉煌浪漫,这与化学中“焰色反应”知识相关。下列说法中正确的是(      )

A:焰色反应均应透过蓝色钴玻璃观察

B:非金属单质燃烧时火焰均为无色

C:所有金属及其化合物灼烧时火焰均有颜色

D:NaCl与Na2CO3灼烧时火焰颜色相同

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D

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    I met Mrs. Neidl in the ninth grade on a stage-design team for a play and she was one of the directors. Almost instantly I loved her. She had an Unpleasant voice and a direct way of speaking,1 she was encouraging and inspiring. For some reason, she was impressed with my work and me.

    Mrs. Neidl would ask me for my 2  . She wanted to know how I thought we should3 things. At first I had no idea how to answer because I knew 4  about stage design! But I slowly began to respond to her 5 . It was cause and effect: She believed I had opinions, so I began to 6  them. She trusted me to complete things, so I completed them perfectly. She loved how 7  I was, so I began to show up to paint more and more. She believed in me, so I began to believe in myself.

    Mrs. Neidl's 8  that year was, "Try it. We can always paint over it 9 !"I began to take10 . I had been so afraid of failing but suddenly there was no failing--only things to be11  upon. I learned to dip my brush into the paint and12  create something.

    The shy, quiet freshman achieved success that year. I was13  in the programs "Student Art Assistant" because of the time and effort I'd put in. It was that year that I14  I wanted to spend the rest of my life doing stage design.

    Being on that stage-design team15  Mrs. Neidl changed me completely. Not only was I stronger and more competent than I had thought, but I also16  a strong interest and a world I hadn't known existed. She taught me not to17  what people think I should do: She taught me to take chances and not be18 . Mrs. Neidl was my comforter when I was upset. Her 19 in me has inspired me to do things that I never imagined20 .