题干

只用下列鉴别方法不能将待鉴别的物质区分开的是(   )
选项待鉴别的物质鉴别方法
A氢气与一氧化碳点燃后观察火焰的颜色
B硬水和软水加肥皂水,振荡,观察产生泡沫状况
C过氧化氢溶液和水加二氧化锰,观察有无气泡产生
D氧气和空气分别向其中伸入燃着的木条,观察燃烧情况

A:A

B:B

C:C

D:D

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答案(点此获取答案解析)

A

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    Over the years, thanks to my life's obstacles, I understood the meaning of faith and the strong will to survive. It was Hurricane Ike that made me fully1the beauty of our strength and a human's motivation to2.

    Mom had a two-week3in summer. While we enjoyed our holiday in Southeast Texas, we didn't realize the fact that Ike4cause months and likely years of “labor”. By September 7th, the “eyes of Texas” were watching Hurricane Ike more5, making the typical mad rush for last-minute hurricane 6. Two days later, both oil and ice were in7 demand.

    In the early hours of September 11th, some neighbors were planning to 8the storm in their homes,9others were making final preparations to get away. At first, we decided to stay. But that afternoon, the Houston-Galveston area would be on the more10side of the storm. Mom and I packed some of our most11belongings in the car and12the East Texas town of Lufkin.

    As Ike pushed farther inland, we13power in Lufkin. On Sunday, our next-door neighbor told us via cell phone that our14had remained well. Our hopes could not have been15. But a few hours later, the neighbors reported that our brick chimney had16, and it was sitting on our living room,17a hole in the roof between two skylights (天窗).

    We wouldn't be allowed to return home18September 17th. I climbed upstairs, and looked toward the hole in the roof which showed a beautiful blue sky. Without hesitation, I shouted, “Wow! A third skylight!” My neighbors could not believe I was making jokes19crying, but20 is always good medicine. It was with that joke that I knew, given time, everything would be okay.