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某化学研究性学习小组拟对一种焰火原料(由两种短周期的常见金属单质Li,Na,Mg,Al组成的合金粉末)进行探究.请完成下列探究报告.

【探究目的】探究该焰火原料的组成

【资料检索】①Mg2+检验方法:取2滴待检液,加入2滴2mol•L﹣1NaOH溶液,再加入1滴镁试剂(Ⅰ)染料(对硝基苯偶氮苯二酚).若出现沉淀并吸附镁试剂(Ⅰ)染料呈天蓝色,表示待检液中含有Mg2+.但Ag+、Cu2+、Fe3+、NH4+会妨碍Mg2+检出

②Mg(OH)2可溶于浓的氯化铵溶液,其他的常见不溶碱难溶于氯化铵

③很多合金是金属互化物,有确定的化学组成

【探究思路】①确定焰火原料所含金属种类;②测定焰火原料的化学式

【实验探究】

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    When I was ten, I was crazy about candy. Whenever in our small-town 1 with my mom, I would run my fingers through my favourite candy on the shelf.

    Once I noticed a man pushing buttons on the ATM machine. He seemed to be hurriedly waiting for his cash to appear. He quickly got a pile of bills and headed out. Curiously I walked over and saw a beautiful $100 bill at the bottom of the machine.2I wanted to believe my magic made the cash appear. I knew the man must have left it behind.

    I held the money in my hand, looking at the number "100" and feeling 3 than I ever had. I thought about putting the money into my pocket. No one would know, but it didn't feel4.So I told my mom what had happened. "We will look for him." she said. We rushed out and found him stepping into his car! We went over and asked if he had left money at the cash machine.

    "Let me 5" he said, pulling out his wallet and bill. "One hundred, two hundred, three...Oh!You're right," he said with surprise. "I'm 6a $100 bill."

    "Here you go," I said, smiling with pride, as if I was a detective who solved a mystery. "Thank you so much," he said. Before saying goodbye, he asked me for my name and address.

    On my way home, my7 was racing. 100 dollars. What could I have done with it? I bet I could have bought a puppy or every single candy bar or something else in town! But now 8 of that would happen. Yet I knew I had done the right thing.

    A few weeks later, I got a box with a note. I opened it to find packages of candy.

    "Dear Felice,thank you very much for returning my $100. Your are a great girl, and I appreciate(欣赏)your 9action. I hope you enjoy this candy. Best wishes, Tom." The candy tasted sweet. Although my act wouldn't always be 10 with candy, it would make a difference to someone. And that was the sweetest part of all.