题干

某温度时,使用一对石墨电极电解饱和Na2SO4溶液,当转移2mol电子时停止电解,析出Na2SO4•10H2O晶体m g,所有数据都在相同温度下测得,下列叙述正确的是(   )

A:电解后溶液质量减少(m+36)g

B:原溶液中Na2SO4的质量分数为 71m161(m+18)

C:若其它条件不变,将石墨电极替换为铜电极,则阴极析出2mol H2

D:若其它条件不变,将石墨电极替换为铜电极,则析出Na2SO4•10H2O晶体仍为m g

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B

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    When you see someone you know, the easiest way to recognize them is by their face—but not everyone can do this. Many people have prosopagnosia, or face blindness, which is a neurological(神经病学的)condition where the part of the brain that recognizes faces fails to develop. It can stop people recognizing partners, family members, friends or even their own reflection. It was once thought to be caused by brain injury (acquired prosopagnosia) but now a genetic link has been proved (development prosopagnosia).

    Acquired prosopagnosia is a very rare but as many as one in 50 people may have developmental prosopagnosia. There's no specific treatment, but training programmes are being developed to help improve facial recognition.

    For many, the situation can be dangerous. I've heard stories of people being robbed by strangers claiming to be family members, or of children wandering off strange men.

    It was only is this century that researchers began to realize exactly how many people in this world were quietly living with the condition.

    Like a blind person who can recognize family members by their footsteps, prosopagnosics are forced to develop unusual ways of discovering who it is they're meeting or talking to. From the obvious markers like hair and voice, to the way one sits, stands or walks, they rely on dozens of means to get through ordinary life.

    Faces are an important part of identity. Not to be recognized feels terrible—it's as if you've been overlooked, like someone's saying you don't matter. But it's nothing to the pain of knowing that you're hurting people's feelings constantly, and yet being completely unaware that you're doing it in the moment. To be alienated(隔离的)from the world of faces is a strange position to be in, but I'm comforted by the thought that articles like this will do a little to help people forgive me and others like me.