探討化學表徵對概念理解和理解監控正確性的影響－以國中化學平衡概念為例

Abstract

本研究旨在利用四階段多重表徵診斷測驗，探討巨觀、微觀和符號表徵對中學生於化學平衡問題的概念理解表現及校準準確度之影響，並分析影響學習者自評理解表現之校準準確度的因素。研究對象為北台灣某國中九年級學生共168位(男生91名、女生77名)，蒐集168份量化資料與17位學生晤談資料進行分析。研究主要發現表徵型態對學生的概念理解及校準準確度有影響，且對高、低學習成就學生呈不同趨勢。在概念理解部份，低學習成就學生以巨觀表現最好，微觀最差。高學習成就學生則是以符號表現最好，微觀最差；此外表徵型態也會影響學生迷思概念類型，對於相同概念以不同表徵呈現問題時，學生所持有的迷思概念類型會因表徵呈現方式的不同而異，使得可能在巨觀表徵時不具有的迷思概念，卻在問題以微觀表徵呈現時出現。在自評理解校準準確度部份，則高、低學習成就學生的趨勢相同，以微觀的監控最準確，巨觀最不準確。而探究影響自評理解校準準確度之因素則發現，學生在進行監控判斷時，以單一因子為判斷依據的比例高於複合因子，此比例於各表徵間無明顯的差異。比較不同表徵下，不同因子對自評理解校準準確度之影響則發現，學生以既有概念為監控依據時，於巨觀及微觀表徵通常監控較準，於符號表徵則否。複合因子在巨觀與符號表徵監控較不準，在微觀表徵則監控較準。

The research aims to utilize a four-tiered diagnostic instrument to explore effects of macroscopic, submicroscopic, and symbolic representations on 9th grade students’ conceptual understanding and calibration accuracy on chemical equilibrium. In addition, factors that influenc calibration accuracy were explored by interviewing case students regarding their bases used for making performance judgments. Participants include168 9th grade students (male 91, female 77) from two junior high schools in northern Taiwan.Findings of the studyshowed that types of chemical representations affect high- and low- achieving students differently on their conceptual understanding, misconceptions, and calibration accuracy. First, low-achieving students performed best on conceptual understanding when diagnostic questions were presented with macroscopic representations but worst when questions were showed with submicroscopic representations. On the other hand, high-achieving students performed best with symbolic representations but worst with submicroscopic representations. In addition, students’ misconceptions may differ when questions were presented in different types of chemical representations. As a result, students' misconceptions may appear when a question was presented with submicroscopic representation but did not show under the macroscopic representation. Regarding calibration accuracy, both high-and low-achieving students showed a similar trend which calibration was more accurate with submicroscopic representation but worst with macroscopic representations. When students made judgments of their perforamcne, they used more single criterion than combining multiple criteria. In detail, judgments of performance were more accurate with macroscopic and submicroscopic representations when existing concepts were used for making judgment.