物質的粒子模型可說是化學知識中最基本的概念，學生對此模型的瞭解將直接影響到關於三態變化、氣體分子動力論、化學反應與溶液概念等主題的學習。由於過去對粒子模型的研究較集中於學生對於「單一粒子經歷三態變化時，其性質有何改變」的想法，因此我們特別針對「兩種粒子均勻混合」的情況，也就是溶液的概念加以研究。學生的認知發展對他們概念學習的成果會產生極大的影響是無庸置疑的，而比例推理能力向作來為評鑑學生的認知發展的指標之一，則學生對概念的學習必然會受到比例推理能力之某種程度的影響，此即為本研究欲探討的主題之一。本研究的重點除了在探討錯誤概念的類型與性質之外，我們更關注的是教學活動的設計。因此我們以國中學生為對象，採用實驗活動作為教學方法，幫助學生經由實際的操作中獲得具體的經驗，以增進其對於較抽象概念的瞭解。同時，我們在後測的內容中加入具有認知衝突之設計實驗教學，希望能提供學生自我協調的機會，從而探討學生是否有概念上的改變。總括來說，本研究有以下目的：(一)以示範性實驗群測法分析學生對於溶液的錯誤概念及其解釋類型。(二)以學生之比例推理能力為自變數，探討其對於學生溶液概念的瞭解與概念改變的影響。(三)比較實驗教學前後，學生對於溶液相關概念的改變情況。
我們的研究主要有以下三點發現：(一)根據本研究樣本的比例推理能力測驗結果得知；本樣本之國三學生在比例推理能力的發展在統計上顯著優於國二學生(F-50.867, P<.001），但是男生與女生在統計上的差異則不顯著（F=0.493, P=.483）。(二)具有比例推理能力的學生在進行實驗教學後，除了在「飽和概念」上沒有明顯的進步之外，其他溶液相關概念的前測與後測的答對率之間均達到統計上的顯著差異（P<.05)；而不具有比例推理能力的學生即使在經過實驗教學後，也僅在「影響濃度的因素」之概念上有明顯的進步（P<.05)。因此從統計上的考驗證明：比例推理能力的有無的確會影響到學生對於溶液概念的理解程度。(三)由學生在各個溶液相關概念上的概念改變的人數發現：接受實驗教學的學生在各個溶液相關概念中的進步人數百分比在統計上大多大於未接受實驗教學者；而且前者的退步人數百分比亦大多小於後者。此外，本研究也將討論學生對於溶液的錯誤概念與及其解釋的類型。

The particulate theory of matter is the most foundamental concept in chemical knowledge. Students' understanding on this model will directly influece their learning abilities concerning the following conceptions, such as phase change, kinetic molecular theory, chemical change and solution concept, etc.. Because the former studies from the literature review mainly focused on students' thinking about how one kind of particle will change its nature while phase is changed. We focused the study of the situation when two different kinds of particles were completely mixed i. e. the concept of solution. Students' cognitive development will undoubtedly have great influence on their concept learning, therefore the proportional reasoning ability has been as an indicator for evaluating students' cognitive stages. Because of the concept of solution included what two kinds of particles were completed mixed, students'understanding of this concept will be influenced by proportional reasoning abilities to a certain degree. Another purpose of this study was to investigate the concept change through designed teaching activities instead of exploring the nature and types of misconception. In order to improve the students' understanding on more abstract concepts, we took laboratory activities as the teaching strategies and expected that how students could gain concrete experience through practical operation. We also used strategies of cognitive conflict in post-test at the same time and expected that the students' concept would changed.
In conclusion, the main purposes of this study were: (1) to analize types and thinking patterns of students' misconceptions, (2) to explore concept change of solution through experimental activities and cognitive conflict. (3) to explore the influence of students' proportional reasoning abilities on their understanding of solution concept and on their concept change.
The main findings of this study were: (1) After laboratory teaching, there was an obvious difference of the percentage of correct responses in the conceptions of solution between pre-test and post-test for students with correct proportional reasoning abilities, except" the concept of saturation", but for students without proportional reasoning abilities, even they did the laboratory work, they only had obvious progress on the concept of " the factors which influenced concentration". From this point of view, proportional reasoning abilities would indeed influence students' understanding on the concept of solution in somewhat degree. (2) From the data of concept change on each related concepts we could find that those who accepted laboratory teaching would have much improvement on each related concept of solution than those who didn't accept this activity, and for the same kind of concept the former students regressed less than the later.