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归纳法是高中化学学习常用的方法之一,某化学研究性学习小组在学习了《化学反应原理》后作出了如下的归纳总结:归纳正确的是(  )

①常温下,pH=3的醋酸溶液与pH=11的NaOH溶液等体积混合,则有c(Na+)+c(H+)=c(OH)+c(CH3COO

②对已建立化学平衡的某可逆反应,当改变条件使化学平衡向正反应方向移动时,生成物的百分含量一定增加

③常温下,AgCl在同物质的量浓度的CaCl2和NaCl溶液中的溶解度相同

④常温下,已知醋酸电离平衡常数为Ka;醋酸根水解平衡常数为Kh;水的离子积为Kw;则有:Ka•Kh=Kw

⑤电解精炼铜时,电解质溶液中铜离子浓度不变.

A:①④

B:①②④

C:①②④⑤

D:①②③④

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A

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    Growing up in one of the poorest communities with most crimes in Los Angeles, US, being raised by a poorly-educated single mother and attending the worst-quality public school, not many people expected much of me, so I chose to expect something of myself.

    On my 12th birthday, I bought a poster of Harvard University to hang in my room. Being at Harvard became my dream: I saw myself attending class in Sanders Theater, studying in Widener Library and eating in Annenberg Hall. Driven by this dream, I kept studying hard. I'd begin my day by asking myself these two questions: “What do I want in my life?” and “Are the things I am doing today going to get me closer to that life?”

    Asking myself the questions gave me the courage to ask over 50 Harvard, students for advice on my application essays; it gave me the energy to study just one more hour on my SATs when others were asleep; and it gave me the determination to apply for just one more scholarship when already refused many times. Moreover, reminding myself of my goal each day made it easy to say no to the same choices my friends made, because they would never get me closer to my goal. I found that even being poor could not take away my power to decide what I choose to do with my life.

    Every day I could feel myself getting closer and closer to my goal as my writing got better, my SAT score increased, and my scholarship offers started coming in. On March 31st, 2011, an email arrived from Harvard. The first word was “Congratulations!”. Tears of joy filled my eyes.

    Who you are today is the result of the decisions you made yesterday, and who you will be tomorrow will be the result of the choices you make today. Who do you want to be tomorrow?