题干

金属与我们生活息息相关.

(1)学校实验室有一批生锈的铁架台,它们生锈的原因是____ ,写出一个用酸除锈的化学方程式 ____ ,例举一种防止铁架台生锈的方法____ .

(2)为了验证铁、锌、铜三种金属的活动性,将打磨后的两根铁丝,分别插入____ 溶液和____ 溶液中,其中产生的明显现象是____ ,由此得出这三种金属的活动性由强到弱的顺序是____ .

(3)金属铬(Cr)和铁的性质十分相似.在氧化物中都能显+3价,写出铬的氧化物的化学式____ .与稀盐酸反应时,在生成的盐中化合价也相同,写出铬与稀盐酸反应的化学方程式____ .

上一题 下一题 0.0难度 选择题 更新时间:2017-10-25 11:05:13

答案(点此获取答案解析)

\u94c1\u4e0e\u6c34\u548c\u6c27\u6c14\u5e76\u5b58\u53d1\u751f\u4e86\u5316\u5b66\u53cd\u5e94,Fe2O3+6HCl\u25502FeCl3+3H2O,\u5237\u6f06,\u786b\u9178\u950c,\u786b\u9178\u94dc,\u786b\u9178\u94dc\u6eb6\

同类题5

阅读短文,完成下列问题。

    In her outstanding book, “Choose the Happiness Habit”, Pam Golden wrote, “Take the story of two twin brothers for example. One grew up and became an alcoholic (酒鬼), while the other became a successful businessman. When asked why he became an alcoholic, the alcoholic replied, “Because my father was a drunk.” However, the successful businessman's answer was also “Because my father was a drunk.” when asked why he succeeded. The same background. The same upbringing (培养). However, the results were quite different. Why? The reason is that they had different choices. The brothers chose different thoughts which formed the situations they found themselves in at last, so they had different experiences.

    There was a time in my life when I thought difficulty was due to “bad luck”. Have you ever heard the saying “When it rains, it pours”? That was my answer when others asked me how things were going on when I was in trouble. So what do you think I got? “RAIN”. More and more “RAIN”. I couldn't understand why bad luck was always with me.

    Pam Golden says, “You're either living in the problem or you're living in the solution.” Now, when I'm faced with what I used to think was a negative (消极的) situation, I use a different way to think about it. I force myself to replace those negative thoughts that make me lose heart in my mind with positive thoughts which encourage me to fight against the difficulty bravely. Sometimes I write down some ideas that may be a solution, which I combine with the lessons I have learned from the bad situations and the difficulties that troubled me in the past, and often, I find a solution to the problem soon. It seems that I should thank the difficulty I met with. The RAIN that poured in my world has become great experiences that provide me with valuable experience, from which I can benefit.

    Now, it doesn't “rain” as much in my life as it used to. In fact, most days are beautiful, cloudless and sunny! Sometimes I do get a rain, but I think it makes me stronger just like the rain helps plants grow up.