MAKING THE MOLECULAR MODELS FROM EASILY OBTAINABLE MATERIALS

Abstract

In order to comprehend the chemical and physical properties of chemical substances, firstly it is needed to understand their three–dimensional structures (that is, their molecular geometries). However, research literature shows that prospective chemistry teachers have difficulties related to the subject. The reason might be that molecules are entities not directly perceived by the sense organs. Moreover, to imagine the three–dimensional structures and draw the three–dimensional structures on paper or board plane, other difficulties are. By making the models of very small structures like molecules, they can be transformed a visual shape. In this study, in order to made the models of all inorganic species (molecules, ions, complexes) whose central atoms have the types “sp, sp2, sp3, dsp3, d2sp3, dp3 and dsp2” of the hybridisation and many organic molecules (alkynes, allenes, alkenes, alkanes, cycloalkanes, pyranoses, furanoses, benzene) by using cheap and easily obtainable materials (carton paper, play–dough and pin with plastic–head), the methods are explained. In addition, in order to help students’ and teachers’ understanding of the basic geometric concepts, it is given place also the geometric shape models in the molecular models.

Keywords

• Chemistry/science/mathematics education, models, molecular geometry, geometric shapes

KOLAY SAĞLANABİLİR MALZEMELERLE MOLEKÜL MODEL YAPIMI

Abstract

Kimyasal maddelerin kimyasal ve fiziksel özelliklerinin kavranabilmesi için, öncelikli olarak onların uzaysal yapılarının, yani moleküler geometrilerinin anlaşılması gerekmektedir. Halbuki, araştırmalar kimya öğretmeni adaylarının konu ile ilgili zorluklar yaşadıklarını göstermektedir. Bunun sebebi, moleküllerin duyu organları ile algılanamaz olmalarıdır. Üstelik, uzaysal yapıların hayal edilmesi, onların üç boyutlu yapılarının kâğıt düzlemine ve/veya tahta düzlemine çizilmesi başka bir zorluktur. Molekül gibi çok küçük yapıların modelleri yapılarak onlar görsel hâle getirilebilir. Bu çalışmada, merkezi atomunun hibrit tipi sp, sp2, sp3, dsp3, d2sp3, dp3 ve dsp2 olan bütün inorganik türlerin (moleküller, iyonlar, kompleksler) ve çok sayıda organik molekülün (alkinler, allenler, alkenler, alkanlar, sikloalkanlar, piranozlar, furanozlar, benzen) modellerinin ucuz ve kolaylıkla sağlanabilir malzemeler (karton kâğıt, oyun hamuru ve plastik başlı toplu iğne) ile yapılması için yöntemler verilmektedir. Ayrıca, molekül modellerinin içinde, öğrencilerin ve öğretmenlerin temel geometrik şekilleri anlamalarına yardımcı olacak geometrik şekil modellerine de yer verilmektedir.

Keywords

• Kimya/fen/matematik eğitimi, modeller, molekül geometrisi, geometrik şekiller

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