问题
问答题 简答题
如何选择缓冲溶液？
答案
参考答案：
（1）缓冲溶液对反应物的测定没有干扰；
（2）缓冲组分的浓度为1：1；
（3）有足够的缓冲容量；
（4）缓冲溶液的PH应在所需的范围内；
（5）组成缓冲溶液的弱碱PKB和弱酸PKA应接近或等于所需的POH值或PH值（PH+POH=14）。
搜题请搜索小程序“爱下问搜题”
如何选择缓冲溶液？
参考答案：
（1）缓冲溶液对反应物的测定没有干扰；
（2）缓冲组分的浓度为1：1；
（3）有足够的缓冲容量；
（4）缓冲溶液的PH应在所需的范围内；
（5）组成缓冲溶液的弱碱PKB和弱酸PKA应接近或等于所需的POH值或PH值（PH+POH=14）。
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| Our English teacher was like a friend to us, and we all liked her. One day she came into the classroom and shouted, "Who did this?"She held up a piece of broken glass and asked, "Who 1 the window? " She seldom became angry. 2 this time she was. I broke the window. I had done 3 by throwing a baseball. I didn't want to admit (承认) it 4 I didn't have enough money to pay for a big window like that. "My father will be 6 , "I thought. At first I didn't 5 my hand, but later something strong in my heart suddenly made me stand up." I did it, "I said 7 . How difficult it was for me to say that! My teacher 8 a book from one of our book shelves and then began walking 9 my desk. I was afraid that she was going to punish (惩罚) me. "I know you like collecting 10 very much," she said, looking down at my 11 face. "Here is the book about collecting stamps that you are looking for. Now, the book is 12 and I shall not punish you. Remember, it's because you 13 the truth." I couldn't believe it! My teacher wasn't punishing me. I didn't 14 to pay for the broken window. And I got my favourite book! As time goes, the book is 15 ,so is my wonderful teacher. But I will never forget the lesson the teacher gave me that day. | ||||
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