titrarion 有咩error 啊????

滴定(titrarion)有很多誤差因數，以下幾項是其中幾個因素：
1. 溫度─滴定所有設定是以室溫20℃為標準，而不同溫度是會影響試劑(reagent)的體積，如屬酸鹼中和實驗，還會影響酸鹼值。
2. 視覺差─不同人所看之刻度(mark)及終點(end point)會有所分別，這會影響讀數之準確性。
3. 儀器誤差─不同級數儀器如滴定管(burette)、移液管(pipette)、量瓶(volumetric flask)都有其誤差，只是高級數較少。
4. 標準液濃度誤差─就算原裝標準液亦會有所誤差，不能做到所標示的濃度。如是自行準備之標準液則誤差更大。

2006-10-17 01:48:59 補充：
5. 人為錯誤─因搖動手勢不正確，移液管、滴定管沒有垂直。6. 儀器及試劑被污染─儀器未經清洗乾淨就使用，試劑混合了其他溶液等。

in indicated titration 由於reaction 的 equivent point 未必同個 end point 一樣 所以choosing indicator 係好重要
至於 thermometric titration , 要減低個heat loss

There are many cases...

One usual case is that if carbon dioxide is produced and its volume is measured, it is usually smaller than the true volume as carbon dioxide is slightly soluble.

And, the indicators, e.g. methyl orange, phenolphalein are slightly acidic, and may affect the titration result.

2006-10-15 20:49:26 補充：
Also, using indicators may not be very accurate indeed. As the color change is so small that may not be very easy to observe, but actually the end point is reached already. You may not notice and continue the titration, until you observe the obvious color change.

錯誤的error