Revista: | Quimica nova |
Base de datos: | PERIÓDICA |
Número de sistema: | 000313336 |
ISSN: | 0100-4042 |
Autors: | Previdello, Bruno Alarcon Fernandes1 Carvalho, Fernando Rodrigues de Tessaro, Andre Luiz Souza, Vagner Roberto de Hioka, Noboru |
Institucions: | 1Universidade Estadual de Maringa, Departamento de Quimica, Maringa, Parana. Brasil |
Any: | 2006 |
Període: | Jun |
Volum: | 29 |
Número: | 3 |
Paginació: | 600-606 |
País: | Brasil |
Idioma: | Portugués |
Tipo de documento: | Artículo |
Enfoque: | Aplicado, descriptivo |
Resumen en inglés | An experiment is proposed that can be included in undergraduate courses of chemistry. The subject is the acidity of organic compounds, which are employed as pH indicators, particularly in acid-base titrations. The indicators used are methyl orange, bromophenol blue and bromocresol green in aqueous medium. The influence of colloidal systems on the equilibrium is evaluated by the pKa. The colloids employed are surfactants like sodium dodecyl sulfate, cetyl-trimethylammonium bromide and a polymeric non-ionic F127 (pluronics). The effect of stabilization promoted by the system on the acidic or basic structureof the indicator establishes the action mechanism of the colloid on the pKa values |
Disciplines | Química |
Paraules clau: | Química orgánica, Educación química, pKa, Experimentos de laboratorio, Indicadores acido-base, Sistemas coloidales |
Keyword: | Chemistry, Organic chemistry, Chemical education, Laboratory experiments, pKa, Acid-base indicators, Colloidal systems |
Text complet: | Texto completo (Ver HTML) |