题干

某同学通过如下流程制备氧化亚铜:

已知:CuCl难溶于水和稀硫酸;Cu2O+2H+=Cu2++Cu+H2O

下列说法不正确的是(   )

A:步骤②中的SO2可用Na2SO3替换

B:步骤③中为防止CuCl被氧化,可用SO2水溶液洗涤

C:步骤④发生反应的离子方程式为2CuCl+2OHˉ Cu2O+2Clˉ+H2O

D:如果Cu2O试样中混有CuCl和CuO杂质,用足量稀硫酸与Cu2O试样充分反应,根据反应前、后固体质量可计算试样纯度

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D

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    It's generally believed that people act the way they do because of their personalities and attitudes. They recycle their garbage because they care about the environment. They pay $5 for a caramel brulee latte because they like expensive coffee drinks.

    It's undeniable that behavior comes from our inner dispositions(性情), but in many instances we also draw inferences about who we are, as suggested by the social psychologist Daryl Bern, by observing our own behavior. We can be strangers to ourselves. If we knew our own minds, why should we need to guess what our preferences are from our behavior? If our minds were an open book, we would know exactly how much we care about the environment or like lattes. Actually, we often need to look to our behavior to figure out who we are.

    Moreover, we don't just use our behavior to learn about our particular types of character — we infer characters that weren't there before. Our behavior is often shaped by little pressures around us, which we fail to recognize. Maybe we recycle because our wives and neighbors would disapprove if we didn't. Maybe we buy lattes in order to impress the people around us. We should not mistakenly believe that we always behave as a result of some inner disposition.

    Whatever pressures there can be or inferences one can make, people become what they do, though it may not be in compliance(符合) with their true desires. Therefore, we should all bear in mind Kurt Vonnegut's advice: “We are what we pretend to be, so we must be careful about what we pretend to be.”