Avaliação da capacidade tamponante - um experimento participativo

Química Nova

César Ricardo Silva¹  José De Alencar Simoni¹ 

[1] ,UNICAMP Instituto de Química Campinas SP

关键词: buffer solution;    buffer capacity;    titration;   

DOI  :  10.1590/S0100-40422000000300019

来源: SciELO

【 摘 要 】

The aim of this work is to show an experiment from which students can learn some of the main characteristics of buffer solutions. A mixture of some acid-base indicators, named as Yamada's indicator, can be used to estimate pH values in an acid-base titration of a buffer, with good approximation. In the experiment it is also possible to verify the relationship between the buffer capacity and the concentrations and the molar ratio of the components of a NH3 / NH4+ buffer solution. The shortage of experiments associated with the relative small importance given to many aspects of buffer solutions, is now explored with simplicity. In the proposed experiments, students prepare buffer solutions by themselves, calculate the pH, understand how acid-base indicators act and learn how buffer solutions work through graph constructed by sharing experimental data.

【 授权许可】

CC BY-NC   
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