Diagnostic Study of Students^ Initial Knowledge as Retention in SN1 and SN2 Reaction Mechanism Lecture
Rinaningsih, Asep Kadarohman

Universitas Negeri Surabaya
Universitas Pendidikan Indonesia

Abstract

The Sorogan-Bandongan Model is an individual lecture model at boarding schools in Indonesia. Before the implementation of the model in the lecture, a diagnosis of students^ initial knowledge should be carried out. Prerequisite concepts that are studied in order to understand SN1 and SN2 reaction mechanism are substitution reaction, nucleophilicity, Lewis acids and bases, electron configuration, orbital filling, hybridization and electronegativity. This study aims to determine whether the Sorogan-Bandongan model is effective to be employed as retention in SN1 and SN2 reaction mechanism lecture. The research method used is Mixed Method with Creswell^s Embedded Experimental Design model. The analysis of the pre test - post test data is qualitatively described. Then, quantitatively, some pre-test data of prerequisite concepts (substitution reaction, nucleophilicity, electron configuration, orbital filling, hybridization, electronegativity) are correlated with some post-test data of SN1 and SN2 reaction mechanism. Qualitatively, it is obtained increased average of 11.07 for mastery of concept. Quantitatively, it is obtained correlation data of 0.45 between the diagnostic test as pre-test with the post-test- reaction substitution with reaction mechanism 0,13- nucleophilicity with reaction mechanism 0.12- Lewis acids and bases with reaction mechanism 0.31- electron configuration with reaction mechanism 0.30- orbital filling with reaction mechanism -0.09- Hybridization with reaction mechanism 0.26- electronegativity with reaction mechanism 0.16. Based on the correlation result, it is found that orbital filling is not considered as prerequisite concept in studying SN1 and SN2 reaction mechanism.

Keywords: diagnosis of initial knowledge, prerequisite concept, reaction mechanism, Sorogan-Bandongan model, individual lecture, retention.

Topic: Chemistry Education