题干

如图是探究分子运动的实验装置图,向盛有约40mL蒸馏水的烧杯中加入5﹣6滴酚酞溶液,搅拌均匀观察溶液的颜色是____;将烧杯中的酚酞溶液分别倒入A、B两个小烧杯中,另取一个小烧杯C,加入约5mL的浓氨水,用大烧杯罩住A、C两个小烧杯,烧杯B置于大烧杯外,见图,几分钟后观察到A烧杯中的现象为A____;出现上述现象的原因是____,说明浓氨水有____性,该实验说明分子的性质是____

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\u65e0\u8272,\u6eb6\u6db2\u53d8\u7ea2\u8272,\u6d53\u6c28\u6c34\u4e2d\u7684\u6c28\u5206\u5b50\u662f\u4e0d\u65ad\u8fd0\u52a8\u7684\uff0c\u5f53\u8fd0\u52a8\u5230A\u4e2d\u65f6\u548c\u6c34\u7ed3\u5408\u6210\u6c28\u6c34\uff0c\u6c28\u6c34\u663e\u78b1\u6027

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    Research suggests that at least 64% of people now spend up to four hours daily of spare time in front of a screen. Just as TV watching has been linked to higher chances of being fat and getting diseases, this extra sedentary time is bad news for our health.

    ⒈Choose outdoor activities over technology

    When you're at home, make it a rule that you can't be online if the sun is shining. Instead, you have to go for a walk, ride a bike, swim or get some other kind of healthy, physical activity for at least an hour before you can pull out your phone or tablet, or take a seat at the computer. This rule should be fit for everyone in your family.

    ⒉Limit social media use

    Social networks have changed computer and mobile use for people of all ages. Whether it's Facebook, Twitter, Instagram or Snapchat. Limit the amount of time you spend on social media. Avoid aimless browsing(浏览) and give your time online a purpose research holidays or catch up on the news of the day. Then log off.

    ⒊Save time for reading

    Challenge yourself to read at least 30 pages of a great book before you check your computer or mobile phone. Pick the right reading material and you'll soon find you've discovered an enjoyable pastime.

    ⒋Create projects for yourself

    It's amazing how much you can achieve when you're not glued to (长时间盯着) a screen. Do a list of one-hour evening projects. Some suggestions are organizing kitchen cupboards, cleaning your bedroom. Then try to do one each evening.