题干

一化学兴趣小组对某月饼包装盒中的“脱氧剂”很好奇,他们观察到“脱氧剂”外包装标注的成分为铁粉、活性炭和氯化钠,打开发现灰黑色的固体中还夹杂着少量红棕色粉末。
【资料获悉】①铁系“脱氧剂”的作用原理是利用铁能被氧气氧化,从而达到除氧保鲜的目的。铁被氧气氧化最终产物为红棕色的Fe2O3(其他产物忽略不计)。
② Fe2O3+3H2SO4== Fe2(SO4)3+3H2O ;Fe + Fe2(SO4)3= 3FeSO4
③“碱石灰的干燥管”可以用来干燥氧气、氢气等气体。
【探究目的】小组同学欲探究该“脱氧剂”是否已经失效,并测定10.00g样品各成分的质量,设计了以下探究实验。
【实验探究】(假设所有操作没有损失)
步骤1:小刚用磁铁接近样品,发现磁铁吸引了部分黑色固体。
步骤2:称取10.00g样品于一烧杯中,加足量水充分搅拌溶解后,过滤,将滤渣洗涤、干燥、称得其质量为8.32g。
步骤3:按如右装置,将得到的8.32g固体与足量稀硫酸反应,用电子秤称得反应前后总质量差为0.11g。

步骤4:将锥形瓶中反应后的液体过滤,并将滤渣洗涤、干燥后,称得其质量为1.20g。
步骤5:分析测算步骤4中所得滤液得知:滤液中溶质是硫酸和硫酸亚铁 ,且最后分离出16.72g硫酸亚铁。


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Lyle's Second Go

    In 1982,when I was coaching the Raiders, the owner of the team talked with me about a possible trade for Lyle Alzado. After watching him on tape,I didn't think he was that good, but the owner felt we could make Lyle better by creating the right environment lor him. We made the1.

    That summer at training camp,Lyle was having a hard time. He had that look in his eyes that many young players and some old players get when things aren't going 2.One morning Lyle came into my office and he looked like he hadn't slept. Here was a huge man, with his head about as3as it could go. We talked, or rather, I listened. The main point was that Lyle felt his career (职业生涯)was over and it would be best for him and for the team if he retired (退役).He apologized for4us since we had just traded for him.

    Lyle was always an emotional person. This is one of the reasons he was a good player. He5all that emotional energy with him, ready to lire out at the snap of the ball (开球).Now he was in front of me, almost crying. I thought for a moment, realizing we had to keep that 6going. Then I went through my reasons why he should not retire. At the end of our talk, I said,“You go out and play your very best, and let us7if you still have it. Personally, I think you do.”

    In January 1984. Tampa Bay Stadium. Super Bowl XVIII. With less than two minutes remaining, we were leading 38-9. We were the world champions of professional football. I saw Lyle,crying like a baby. I had to turn away quickly,or I would have joined him in 8.

    I remembered that morning in my office, and what Lyle, and what the Raiders, had achieved since he came to us. If Lyle hadn't given his career another shot, he wouldn't have had this victory. Maybe the Raiders wouldn't have had this victory. During that moment, I felt one of the greatest satisfactions of my coaching career.