Polarographic and Spectrophotometric Study of Lead Complexes w
نویسنده
چکیده
Foram estudados aspectos experimentais e teóricos sobre o comportamento do complexo de chumbo com dietanolditiocarbamato (DEDC), em solução. A reação ocorre através da formação de um precipitado amarelo, o qual é solúvel em excesso de ligante e alguns solventes polares. Os resultados das análises, elementar e gravimétrica, mostram uma relação estequiométrica de 1:2 (Pb:DEDC), comprovada nos estudos potenciométricos. A aplicação da equação de Lingane, nas formas estendida e simplificada, foi avaliada na determinação da constante de estabilidade global e do número máximo de coordenação, por Polarografia convencional. Os resultados indicam que são coordenados três ligantes, com uma constante de estabilidade, βMLn , aproximadamente igual a 4 x 10. Estes resultados mostram boa concordância com outros prévios resultados, obtidos por potenciometria, para o mesmo sistema. Estudos cinéticos-espectrofotométricos foram conduzidos para avaliar a estabilidade do ligante puro e complexado em meio ácido.
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