题目

 请写出下列变化的化学方程式： (1)硫酸铜溶液和氯化钡溶液反应：________________________________________； (2)在稀盐酸中滴加氢氧化钠溶液：________________________________________。 答案：【答案】    (1). CuSO4+BaCl2=BaSO4↓+CuCl2    (2). NaOH+HCl=NaCl+H2O 【解析】本题考查了常见化学反应的方程式，书写时注意规范。 (1)硫酸铜溶液和氯化钡溶液反应生成硫酸钡和氯化铜，反应的化学方程式是：CuSO4+BaCl2=BaSO4↓+CuCl2； (2)稀盐酸与氢氧化钠反应生成氯化钠和水，反应的化学方程式是：NaOH+HCl=NaCl+HQuit while you're aheadI am one of those people who are terrible at saying no．I take on too many projects at once, and spend too much of my time doing things I'd rather not be doing．I get work done, but it's not always the best I can do, or the best way I could spend my time． That's why my newest goal, both as a professional and a person, is to be a quitter．Being a quitter isn't being someone who gives up, who doesn't see important things through to the end．I aspire （渴望?） to be the opposite of that．The quitter I want to be is someone who gets out when there's no value in what he's doing, or when that value comes at the expense of something more important．A friend of mine once told me, "I knew I was an adult when I could stop reading a book, even after getting 500 pages into it．" Strange though it sounds, we all tend to do this．We get involved in something, realize we don't want to be a part of it, but keep on going．We say "Well, I've already invested so much time in this, I might as well stick it out．"I propose the opposite: quit as often as possible, regardless of project status or time invested．If you're reading a book, and don't like it, stop reading．Cut your losses, realize that the smartest thing to do is to stop before your losses grow even more, and quit．Instead of reading an entire book you hate, read half of a bad one and half of a good one．Isn't that a better use of your time?Step back for a second．Let's learn how to say "no" at the beginning, or in the middle, and free up more of our time to do the things we'd like to be doing, and the things actually worth doing． Saying no is hard, and admitting a mistaken yes is even harder．If we do both, we'll start to make sure that we're spending our time creating value, rather than increasing our losses．Let's be quitters together．【小题1】The author wants to be a quitter, because he _____．A．hopes to improve his personalityB．wishes to have more time for relaxationC．expects to make more efficient use of his timeD．has found it hard to do several things at one time【小题2】In what circumstances does the author suggest quitting is a good idea?A．When you feel tired and need a rest．B．When you know a task cannot be finished．C．When you meet with difficulties along the way in your life．D．When you realize what you are doing is not worth the time．【小题3】If you stop reading a book you hate, the author might think that ______．A．you are wise to cut your lossesB．it's a pity that you have wasted so much timeC．you should finish a book that you have startedD．you should regret choosing the wrong book【小题4】The message the author tries to convey is to ______．A．learn to say noB．live your life to the fullestC．create more valueD．stop doing many things at once