题目

无标签试剂瓶中的一种黑色不溶于水的固体可能是硫化铜或者是硫化亚铜。查阅资料可知：硫化铜（CuS）和硫化亚铜（Cu2S）在空气中加热分别发生下列化学反应：2CuS+3O2 2CuO+2SO2Cu2S+2O2 2CuO+2SO2 （1） Cu2S中铜元素的质量分数为。 （2） 某同学取瓶中黑色固体称得P（g），选用合适装置进行充分加热灼烧，测得剩余固体质量为W（g）。结合以上两反应分析，若P/（P-W）=6，则瓶中黑色固体的组成成分为。用所给词的适当形式填空 (10) 1.---Where did you______ (study) last night? ---No, I__________(help)my mother_______(clean) the room. 2.Mike goes to see his grandparents _________(one) a week. 3.To keep healthy，I decide _______ (exercise) half an hour every day 4.He is         (funny) than the other students in his class. 5.The boy enjoys         (swim) very much. 6.His mother often makes him        (clean) his room on weekends. 7.It’s necessary for us         (learn) English well. 8.I’m           (good) at physics than my sister. 9.Dumpling House is          (cheap) restaurant in the city. 10.I think Xi Yangyang is as         (famous) as Mikey Mouse.