Voltammetric analysis of weak acids with microelectrodes

Detalhes bibliográficos
Autor(a) principal: Canhoto, Carla
Data de Publicação: 2004
Outros Autores: Matos, Mara, Rodrigues, Astride, Geraldo, M. Dulce, Bento, M. Fátima
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
Texto Completo: http://hdl.handle.net/1822/1959
Resumo: The role of H+ on the steady-state voltammetric limiting current (IL) of weak acids (HA) reduction was studied considering results from either lactic acid or acetic acid solutions at constant pH. For solutions with pH > pKa or pH near pKa the [H+] effect on the IL vs cHA slope was important even when the H+ current contribution was minor. In opposition, when pH << pKa high H+ current contributions were found nevertheless the IL vs cHA slope was almost insensitive to pH. A general relationship between IL and cHA was derived considering both the H+ current contribution and the dissociation extent. This equation allows the analytical determination of weak acids, alone or in the presence of strong acids, from experimental IL and pH. Acids identification can also be performed through the presented expression, following the IL susceptibility to pH at constant cHA.
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spelling Voltammetric analysis of weak acids with microelectrodesWeak acids analysisMicroelectrodesVoltammetryScience & TechnologyThe role of H+ on the steady-state voltammetric limiting current (IL) of weak acids (HA) reduction was studied considering results from either lactic acid or acetic acid solutions at constant pH. For solutions with pH > pKa or pH near pKa the [H+] effect on the IL vs cHA slope was important even when the H+ current contribution was minor. In opposition, when pH << pKa high H+ current contributions were found nevertheless the IL vs cHA slope was almost insensitive to pH. A general relationship between IL and cHA was derived considering both the H+ current contribution and the dissociation extent. This equation allows the analytical determination of weak acids, alone or in the presence of strong acids, from experimental IL and pH. Acids identification can also be performed through the presented expression, following the IL susceptibility to pH at constant cHA.POCTI/QUI/ 39525/2001.ElsevierUniversidade do MinhoCanhoto, CarlaMatos, MaraRodrigues, AstrideGeraldo, M. DulceBento, M. Fátima2004-082004-08-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/1959eng"Journal of electroanalytical chemistry". 570:1 (2004) 63-67.0022-072810.1016/j.jelechem.2004.03.015info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T12:07:19ZPortal AgregadorONG
dc.title.none.fl_str_mv Voltammetric analysis of weak acids with microelectrodes
title Voltammetric analysis of weak acids with microelectrodes
spellingShingle Voltammetric analysis of weak acids with microelectrodes
Canhoto, Carla
Weak acids analysis
Microelectrodes
Voltammetry
Science & Technology
title_short Voltammetric analysis of weak acids with microelectrodes
title_full Voltammetric analysis of weak acids with microelectrodes
title_fullStr Voltammetric analysis of weak acids with microelectrodes
title_full_unstemmed Voltammetric analysis of weak acids with microelectrodes
title_sort Voltammetric analysis of weak acids with microelectrodes
author Canhoto, Carla
author_facet Canhoto, Carla
Matos, Mara
Rodrigues, Astride
Geraldo, M. Dulce
Bento, M. Fátima
author_role author
author2 Matos, Mara
Rodrigues, Astride
Geraldo, M. Dulce
Bento, M. Fátima
author2_role author
author
author
author
dc.contributor.none.fl_str_mv Universidade do Minho
dc.contributor.author.fl_str_mv Canhoto, Carla
Matos, Mara
Rodrigues, Astride
Geraldo, M. Dulce
Bento, M. Fátima
dc.subject.por.fl_str_mv Weak acids analysis
Microelectrodes
Voltammetry
Science & Technology
topic Weak acids analysis
Microelectrodes
Voltammetry
Science & Technology
description The role of H+ on the steady-state voltammetric limiting current (IL) of weak acids (HA) reduction was studied considering results from either lactic acid or acetic acid solutions at constant pH. For solutions with pH > pKa or pH near pKa the [H+] effect on the IL vs cHA slope was important even when the H+ current contribution was minor. In opposition, when pH << pKa high H+ current contributions were found nevertheless the IL vs cHA slope was almost insensitive to pH. A general relationship between IL and cHA was derived considering both the H+ current contribution and the dissociation extent. This equation allows the analytical determination of weak acids, alone or in the presence of strong acids, from experimental IL and pH. Acids identification can also be performed through the presented expression, following the IL susceptibility to pH at constant cHA.
publishDate 2004
dc.date.none.fl_str_mv 2004-08
2004-08-01T00:00:00Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://hdl.handle.net/1822/1959
url http://hdl.handle.net/1822/1959
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv "Journal of electroanalytical chemistry". 570:1 (2004) 63-67.
0022-0728
10.1016/j.jelechem.2004.03.015
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Elsevier
publisher.none.fl_str_mv Elsevier
dc.source.none.fl_str_mv reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
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instname_str Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron_str RCAAP
institution RCAAP
reponame_str Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
collection Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
repository.name.fl_str_mv
repository.mail.fl_str_mv
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