1.why Na2CO3 can be titrated against HCl ?
2.Na2CO3 is not alkali ,why methyl orange can be used as indicator for the titration?
chem titration
2014-08-24 7:23 pm
回答 (2)
2014-08-25 2:24 am
✔ 最佳答案
The answer is as follows :圖片參考：https://s.yimg.com/lo/api/res/1.2/a.S2aLDVW63jZhXQwaIF8A--/YXBwaWQ9dHdhbnN3ZXJzO3E9ODU-/https://farm6.staticflickr.com/5570/14831204797_2510f8ee05_o.png
https://farm6.staticflickr.com/5570/14831204797_2510f8ee05_o.png
參考: pingshek
2014-08-24 8:57 pm
Na₂CO₃(aq) → 2Na⁺(aq) + CO₃²⁻(aq)
CO₃²⁻(aq) + H₂O(l) ⇄ HCO₃⁻(aq) + OH⁻(aq)
H⁺(aq) + OH⁻(aq) → H₂O(l)
HCO₃⁻(aq) + H₂O(l) ⇄ H₂CO₃(aq) + OH⁻(aq)
H⁺(aq) + OH⁻(aq) → H₂O(l)
pH of Na₂CO₃(aq) > 7
CO₃²⁻(aq) + H₂O(l) ⇄ HCO₃⁻(aq) + OH⁻(aq)
H⁺(aq) + OH⁻(aq) → H₂O(l)
HCO₃⁻(aq) + H₂O(l) ⇄ H₂CO₃(aq) + OH⁻(aq)
H⁺(aq) + OH⁻(aq) → H₂O(l)
pH of Na₂CO₃(aq) > 7
收錄日期: 2021-04-27 20:41:53
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140824000051KK00039