4.6g某物质在氧气中完全燃烧生成4.4g二氧化碳和3.6g水,则该物质的组成为

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问题:

4.6g某物质在氧气中完全燃烧生成4.4g二氧化碳和3.6g水,则该物质的组成为[ ]

A.只含碳、氢元素

B.一定含碳、氢、氧三种元素

C.无法确定

D.一定含碳、氢元素,可能含氧元素

考点:物质组成元素的质量分数
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动词填空 用括号内所给动词的适当形式填空,并将答案写在标有题号的横向上。(本大题共8小题,每小题1分,共8分)

小题1: —Isn’t it time for you to go to bed, Mike?

—I ____________ (reply) to my classmates’ e-mails all afternoon, so I have to do my homework now.

小题2:The students had no choice but _____________(stay )in the classroom because of the heavy haze(雾霾).

小题3:The boy’s abilities to organize class activities may ____________ (doubt) if he fails again tomorrow.

小题4:She said nothing and finally ____________ (accept) the fact that she didn’t pass the maths exam.

小题5:—Mum, can I go to the zoo with Jack?

—When your homework ____________ (finish), you can.

小题6:Our teacher often says that ___________(plan) ahead can help us a lot.

小题7:He told me that he _______________ (not hear) from his father since last November.

小题8:In his last seven games, Bale from Real Madrid(皇马) _______________ (score)eight goals.

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小明骑自行车沿公路以akm/h的速度行走全程的一半,又以bkm/h的速度行走余下的一半路程;小刚骑自行车以akm/h的速度走全程时间的一半,又以bkm/h的速度行走另一半时间,则谁走完全程所用的时间较少?(  )

A.小明

B.小刚

C.同时问

D.无法确定

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依据合同法有关合同种类的理论,买卖合同不属于()。

A.实践合同

B.诺成合同

C.有偿合同

D.双务合同

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简述岩石单轴压缩变形试验的试验方法、过程、和资料整理。

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