题干

NA代表阿伏伽德罗常数,下列叙述错误的是

A:在H2O2+Cl2=2HCl+O2反应中,每生成32 g氧气,则转移2 NA个电子

B:10mL 1 mol·L-1的H2SO4,用水稀释至100 mL,H2SO4的浓度为0.1 mol·L-1来源:Z*xx*k.Com

C:分子数为NA的CO、C2H4混合气体体积约为22.4 L,质量为28 g

D:一定温度,1 L 0.50 mol·L-1NH4Cl溶液与2 L0.25mol·L-1NH4Cl溶液含NH4物质的量不同

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C

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    It started as a special day for Wesley Autrey, a 50-year-old construction worker in New York City. It was about 12:45 P.M., and he was waiting on a subway platform (月台) to take his daughters home before he went to work. He suddenly noticed a man nearby have convulsions (抽搐) and fall down suddenly. Mr. Autrey and two women went to help the stranger. The man, Cameron Hollopeter, managed to get to his feet, but then stumbled (绊倒) at the edge of the platform and fell onto the subway tracks. Mr. Autrey looked up and saw the lights of the subway train coming near through the tunnel.

    Mr. Autrey jumped onto the track immediately. He realized that he didn't have time to get Mr. Hollopeter and himself back up on the platform before the train arrived, so he lay on top of the man and pressed down as hard as he could. Although the driver tried to stop the train before it reached them, he couldn't. Five cars passed over them before the train finally stopped. The cars had passed only inches from his head.

    New York loves a hero. Mr. Autrey became an overnight hero and was named the “Subway Superman”. New York City Mayor Michael Bloomberg gave him the Bronze Medallion, the city's highest honor. He was asked to appear on several TV talk shows. He was also rewarded with money and gifts, such as $10,000 from Donald Trump, a $5,000 gift card from the Gap clothing store, a new Jeep, and Beyonce concert tickets.

    How did Autrey react (反应) to all this? He said, “I don't feel like I did anything great; I just saw someone who needed help. I did what I felt was right”.