x*****8 发帖数: 10683 | 1 【 以下文字转载自 Military 讨论区 】
发信人: xiaxie8 (All I want for Christmas is Xiaoyun!), 信区: Military
标 题: 最讨厌学生和我争论
发信站: BBS 未名空间站 (Tue Dec 6 22:54:31 2016, 美东)
上次一个美女学生AP Chemistry预测盐溶液的pH。
其中一道题是: Na2SO4
我告诉她:It's exactly 7 since NaOH is a strong base, while H2SO4 is a
strong acid.
当时她将信将疑。
今天她毫不客气地说:I think you were wrong last time. My friends and my
teacher all told me the pH should be higher than 7 since the conjugate acid
of SO4 2- is HSO4 -, which is a weak acid, while the conjugate base of Na +
is NaOH, which is a strong base.
我厌恶地说:If you don't agree with what I said, then please find a
different teacher!
我心里很清楚我是正确的,她的同学和老师都错了!硫酸钠是强酸硫酸和强碱氢氧化钠
形成的盐,pH当然是中性的。你不能因为硫酸的第一步离解算强酸而硫酸的第二步离解
算弱酸就得出硫酸钠水溶液略偏碱性的错误结论!
不听我话的,再漂亮我也不教! |
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