题目

    According to the doctors, most adults need about seven to eight hours of sleep each night to feel great during the day.  51      Are you getting enough sleep each night? See how many of the six signs below describe you. This will give you a good idea of whether you need more sleep or not.     ①____52_______     If you’re getting enough sleep, you should be able to wake up on time without a morning alarm. Hitting the button several times before getting up is a clear sign of sleep loss.     ②You’re driving, sleepy and tired.     Falling asleep at the wheel 在宏观、微观和符号之间建立联系是学习化学的基本方法。 (1)下列为A、B、C、D 的原子或离子的结构示意图。 ①B的原子结构示意图中X为             ; ②若D的元素符号为S,则D表示的微粒符号是               ; ③分析A、C的原子结构,你认为A与C具有相似化学性质的原因是                   。 (2)下图为处理汽车尾气化学反应微观示意图,其中A、B、C、D表示4种物质,A和B在一定条件下反应可生成C和D。 反应前 反应后 A B C D ④根据上述微观示意图,处理汽车尾气后生成的C和D的质量比为                     。
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