25.0ml , 0.35M HCOOH(aq) 與 25.0ml , 0.20M KOH(aq)混合後
溶液之PH值為若干? (已知HCOOH(aq)之Ka=1.77 * 10 ^(-4))
混合溶液PH值計算
2014-02-09 2:48 am
回答 (2)
2014-02-09 3:11 am
✔ 最佳答案
HCOOH + KOH <==> H₂O + HCOO⁻ + K⁺After reaction :
[HCOOH] = [(0.35)(25/1000) - (0.20)(25/1000)]/[(25+25)/1000] = 0.075 M
[HCOO⁻] = (0.20)(25/1000)/[(25+25)/1000] = 0.1 M
HCOOH <==> H⁺ + HCOO⁻
Ka = 1.77X10⁻⁴ = [H⁺][HCOO⁻]/[HCOOH]
[H⁺] = (1.77X10⁻⁴)[HCOOH]/[HCOO⁻] = (1.77X10⁻⁴)(0.075)/(0.1) = 1.33X10⁻⁴ M
pH = 3.88
2014-03-02 8:23 am
收錄日期: 2021-04-27 20:31:50
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140208000010KK02556