题干

下列对对应现象的描述与离子方程式都正确的是(   )

A:金属镁与稀盐酸反应:有气体生成,Mg+2 H++2Cl═MgCl2+H2

B:氯化钡溶液与硫酸反应:有白色沉淀生成:SO42+Ba2+═BaSO4

C:碳酸钠溶液与盐酸反应:有气泡逸出:Na2CO3+2 H+═2Na++CO2↑+H2O

D:过量铁粉与氯化铜溶液反应:溶液由蓝色变成浅绿色,同时有红色固体生成:Fe+Cu2+═Fe3++Cu

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B

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    My 17-year-old daughter went off to college and having her away from home brought back memories of watching Peter Pan when she was little. In the classic TV production, one scene in particular impressed me: when Mrs. Darling puts her children into bed. As she turns off the last of the night light, she takes one last look at the bedroom and says, “Dear night lights, protect my sleeping children.” As a mother, I know how much she loves her children.

    It has been several weeks since we took our daughter to college and she seems to be adjusting well after a short period of homesickness. For us, though, it's another story. Like most parents, I love checking in on my children at night. But now she's gone, and I find nighttimes the hardest. I miss her most at night.

    In my neighborhood, most of the parents whose kids are off to college are dealing with similar melancholy. My husband is filled with anxiety. One friend talked about getting this sick feeling in her stomach as she prepared for the college drop-off. We complained that many of us were too busy to truly enjoy being with our children while we had them.

    For us moms, seeing Toy Story 3 only made the sadness worse as we watched the character Andy, who is the same age as our kids, say goodbye to his childhood as he prepares to leave for college. And it's not just “first-time” parents like me. Two moms who have kids already well into college said the separation didn't get any easier. “You feel like something has been taken away from inside you” said one of them.

    I imagine things will get easier with time, especially as I see my daughter adjust to college life. Meanwhile, as I keep my cell phone close to me in bed and text my daughter goodnight and sweet dreams every night, I like to think that messages serve as a night light that keeps her safe.