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    We get it: You're tired. You're busy. And your shoes are away over there. Excuses are OK sometimes, but not every day—and especially not today. So put on your sneakers, get up off the couch, and let us kick your excuses to the curb (路边).

    “I…dislike…panting !”

    Being really out of breath may mean you're trying too much too soon, which will kill your confidence. But you don't have to be huffing and puffing to get a workout. Being active doesn't have to mean high-intensity. It's just about moving.

    “I hate exercise.”

    It may seem unbearable, but you just have to get started. Exercise releases endorphins (your brain's own feel-good chemicals), which can be habit-forming. What' s the best exercise? The one you'll do regularly. So you may hate running. Don't run! Ride your bike or just dance. Even cleaning your room is active. As long as you're moving and getting your blood pumping, it counts. So get creative.

    “I don't have time.”

    You may not have lots of time to spare when you're busy with schoolwork, but we bet you can find 10 minutes. Bonus: An activity break will send oxygen to your brain, making you super-alert and more creative too. Famous thinkers like Aristotle and Steve Jobs liked “walking meetings," and you can follow in their footsteps by moving around while you brainstorm about a tough task or memorize your English vocabulary.

    “I never see results!”

    Even if you train with the help of a professional, you won't see results right away. But you will feel them almost immediately. Don't focus on how your body looks—focus on how you feel. Keep a journal of when you exercise (or don't) and how you feel that day: Stressed? Focused? Tired? When you start noticing the amazing effects of exercise, you'll have no excuses.

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同类题4

某研究小组在实验室探究氨基甲酸铵(NH2COONH4)分解反应平衡常数和水解反应速率的测定.

(1)将一定量纯净的氨基甲酸铵置于特制的密闭真空容器中(假设容器体积不变,固体试样体积忽略不计),在恒定温度下使其达到分解平衡:NH2COONH4(s)⇌2NH3(g)+CO2(g).

实验测得不同温度下的平衡数据列于下表:

温度(℃)

15.0

20.0

25.0

30.0

35.0

平衡总压强(kPa)

5.7

8.3

12.0

17.1

24.0

平衡气体总浓度(×10﹣3mol/L)

2.4

3.4

4.8

6.8

9.4

①可以判断该分解反应已经达到化学平衡的是____ 

A.2v(NH3)=v(CO2)B.密闭容器中总压强不变

C.密闭容器中混合气体的密度不变D.密闭容器中氨气的体积分数不变

②根据表中数据,列式计算25.0℃时的分解平衡常数:____ 

③取一定量的氨基甲酸铵固体放在一个带活塞的密闭真空容器中,在25℃下达到分解平衡.若在恒温下压缩容器体积,氨基甲酸铵固体的质量____ (填“增加”、“减小”或“不变”).

④氨基甲酸铵分解反应的焓变△H ____ 0,熵变△S____ 0(填>、<或=).

(2)已知:NH2COONH4+2H2O⇌NH4HCO3+NH3•H2O.该研究小组分别用三份不同初始浓度的氨基甲酸铵溶液测定水解反应速率,得到c(NH2COO)随时间变化趋势如图所示.

⑤计算25℃时,0~6min氨基甲酸铵水解反应的平均速率____ 

⑥根据图中信息,如何说明水解反应速率随温度升高而增大:____