题干

小刚同学在实验室发现一瓶长期存放的氢氧化钙固体.对此他提出一个问题:这瓶氢氧化钙固体是否变质?

小刚认为氢氧化钙可能变质所依据的化学原理是(用化学方程式表示):____

猜想:①该固体未变质;②该固体部分变质;③该固体完全变质.

设计实验:

操作步骤

现象

结论

____

有气泡产生

证明该固体已经发生变质

②另取少量瓶中的白色粉未加入水中后,再取少许上层清液加入无色酚酞试液

____

证明该固体未完全变质

结论:通过现象分析,小刚确定猜想②成立.

上一题 下一题 0.0难度 选择题 更新时间:2018-11-01 09:46:38

答案(点此获取答案解析)

Ca(OH)2+CO2═CaCO3↓+H2O,取少量白色粉末于试管中,加稀盐酸,酚酞(溶液)变红

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    Changes that will help you get more done than ever before

    Win tomorrow today. All it takes is setting aside five minutes every evening before you end your work to establish the one goal you will accomplish tomorrow. Sometimes, the hardest part of getting things done is deciding which thing to work on first. If this decision making has to happen first thing in the morning, it can create a block to progress, which is no way to start your day. By giving yourself a head start the night before, you're allowing your most productive work hours-in the morning—to be used to the fullest by not having to wonder about on choose what you'll work on first.

    Having a morning routine is one of the best things you've done for yourself. It not only helps you set your day up to be successful by gaining great power first in the morning, but it also allows you to guarantee that you are going to get a set number of things done right away. This way, no matter what your day brings, you should keep in mind that your health and nutrition are the most important. Your morning routine includes a workout, drinking water, meditation(冥想), and ensuring you get the nutrients you need to perform at a high level all day.

    One of the common mistakes people make is to focus entirely on whatever task is next on their list and promise not to move or pause until it's done. Tasks will expand to the time assigned. Instead, try to be inspired from successful people and setting up timed periods for both focused work and breaks. Establishing sections where you have a set amount of focus time followed by a set amount of refresh time prevents you from being distracted(注意力不集中的)and helps you make great progress on the tasks and projects you're working on.

    Being extremely future-focused and ambitious is great, but if you're always moving from one task to another, you could be missing out on a big growth opportunity. In order to learn what's working and what's not working, you need to spend time reflecting. Set aside some time at least every 10 days to reflect on the good, the bad, and everything in between. When you can identify what's working, you'll know what to double down on. You'll also be able to identify the things that are holding you back from getting where you want to go, and to think out solutions for those struggles in order to remove them in the future.

    If you really want to get more done, you have to stop focusing on what you can't do, and start focusing on everything that's going right. Being grateful will not only increase your happiness factor, it will also make you more productive. When you have a positive attitude and take time out to recognize everything you have to be grateful for, you're able to focus on the many things you have accomplished, you're more likely to make progress and get more done.

“ Changes that will help you get more done than ever before

Plan in

____

Set aside five minutes every evening to establish the one goal you will accomplish tomorrow. It will block your progress if you decide what to do first and what to do next the next morning.

It can make your time be____ used by giving yourself a head start the night before.

Adjust your morning

routine

It helps you set your day up for ____ by gaining great power first in the morning.

It also allows you to guarantee that you are going to get a set number of things done right away.

No matter how you arrange your day, the most important thing is your health and ____

____work into

sections

•Take ____ from successful people and set up timed periods for both focused work and breaks.

•Establishing sections helps you____ distractions and make great progress on the tasks and projects you're working on.

Make time for 10-day recaps (重述要点)

•You need to allow ____ time to learn what's working and what's not working.

•Set aside some time at least every 10 days to reflect on things whether they are good or bad.

Be thankful

____ what you can't do and focus on what you can do.

•Being grateful will make you feel ____ and increase your productivity.