Chemistry lecturers' perceptions of “critical barriers” to successful solving of acid-base titration problems

Abstract

Using constructivist theory and knowledge components as a theoretical framework, this paper reports lecturers' perceptions of prior knowledge needed for solving a sample acid-base titration problem involving the neutralization of a conjugate base of a weak acid with a strong acid. Twelve participants were engaged for the study. Their participation in this research was voluntary. Semi- structured interviews were employed as the main instrument for collecting statements about prior knowledge required for solving a sample acid-base titration problem. The transcripts of the interview session were analysed using coding categories. Two types of coding were employed, namely: (1) pre-coding (applicable to the close-ended questions) and (2) researcher-generated coding (applicable to the open-ended questions). These techniques were trialed and found to elicit suitable data in the pilot project. Two independent raters coded the complete transcript of individual lecturers and reliability between the two coders was determined to be 86% using simple agreement analysis. Following application of the qualitative coding scheme to the data collected, frequency counts for each item in the four different knowledge categories (factual, conceptual, procedural, metacognitive) were generated and percentages computed. To help illuminate this analysis, different perceptions of prior knowledge needed for solving an acid- base problem used in this study were reported as a diagrammatic representation. Implications for chemistry teaching are also discussed.

Keywords:

• prior knowledge
• cognitive structure
• knowledge components
• acid-base titration problems
• Teachers' perceptions