Nine Hypothetical Problems for Linkage between Qualitative Analysis and Stoichiometric Calculations
Nine Hypothetical Problems for Linkage between Qualitative Analysis and Stoichiometric Calculations

Summary/Abstract: On the science or the chemistry education, it is one from the most important problems for both the science teachers and the students to design the linkage between ones information and other information as well. The aim of this study is hypothetically to model the linkage between the qualitative analysis and the quantitative analysis with the chemical calculations. For this aim, it is preferred the precipitation reactions of first group cations (Ag1+, Pb2+,Hg22+ ) with HCl solution that is the group reagent in the qualitative analysis of inorganic samples in this study. On these precipitation reactions, it is offered the three sub model for teaching how to calculate the quantity of precipitate if the quantities of one or two reactants are given for the quantitative analysis. These sub models are consecutively called First Model, Second Model and Third Model. First Model: The aim of First Model is to teach how to calculate the mass of precipitate when the molarity and the volume of the solution of only one reactant is given in the problems. Second Model: The aim of Second Model is to teach how to calculate the mass of precipitate if two reactants react completely when the molarities and the volumes of the solution of them are given in the problems. Third Model: The aim of Third Model is to teach how to calculate the mass of precipitate if one of two reactants reacts completely and other remains unreacted when the molarities and the volumes of their solutions are given in the problems. The solutions of problems have been done by two different methods that are known as by the using formula and by the conversion factor. It can be said that the models are hypothetically suitable to investigate the relations between the qualitative analysis and the quantitative analysis with the chemical calculation in this context the reactions of first group cations with HCl that is the group reagent of them. The precipitation reactions are directly the linkage with gravimetric analysis and Mohr, Fajans and Volhard methods in this context of volumetric analysis as well. Keywords: analytical chemistry education, qualitative analysis, quantitative analysis, quantitative precipitation, stoichiometry, chemical calculation, limiting reagent

• Details
• Contents