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This data article is associated with the work “Ecofriendly synthesis of Zn-abietate complex derived from Pinus elliottii resin and its application as an antibacterial pigment against S. aureus and E. coli ”. The characterization data of the Zn-abietate complex obtained from Pinus elliottii resin and their reactional intermediary (Na-abietate) are reported. The Na-abietate was prepared with purified Pinus resin and sodium hydroxide (≥ 99%) in a stoichiometric ratio of 1:1. For the Zn-abietate synthesis was used ZnSO 4 and Na-abietate solutions were at mild temperature and stirring without using organic solvents to ensuring the green character of the synthesis. Spectroscopic and structural characterization was consistent with an octahedral complex involving three carboxylate ligands per metal ion. X-ray photoelectron spectroscopy (XPS) analysis of the Na-abietate salt confirms the presence of carbonyl groups, carbon-oxygen atoms simple bonds (O-C/O=C), and carboxylate groups oxygen atoms (O-C=O). Analysis of the Zn LMM Auger, for the Zn-abietate complex, indicates the presence of zinc atoms with oxidation state Zn 2+ , this is supported by the distance between Zn 2p 3/2 and 1p 1/2 in the XPS spectrum. Together, these data will be useful for the structural representation of the samples.

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In this study, raw smectite (Sm), from the Guarapuava–Parana–Brasil region, was saturated with copper ions (Cu-Sm) by ion exchange and the samples Sm and Cu-Sm were used in crystal violet (CV) adsorption and applied as an antimicrobial and antifungal hybrid pigment. Samples (Sm and Cu-Sm) were used to remove crystal violet (CV) dye from aqueous media, simulating wastewater. Samples after use as adsorbents were characterized and named smectite/adsorbed dye (Sm/Dye) and copper smectite/adsorbed dye (Cu-Sm/Dye); and they were applied as hybrid pigments with antimicrobial action. The Sm and Cu-Sm were characterized by X-ray diffractometry (XRD), energy dispersive X-ray fluorescence (EDXRF), vibrational spectroscopy (FTIR), Zeta potential (ζ), scanning electron microscopy (SEM), and colorimetry (CIE L*a*b*), enabling the identification of the presence of intercalated copper ions and on the smectite surface. The adsorption assays were carried out to evaluate the effects of initial dye concentration and contact time. Tests for application as a hybrid pigment showed good compatibility with commercial white paint being applied on plaster blocks and later photoaging and chemical stability tests were performed in acid and basic environments, both were discussed by colorimetry (CIE L*a*b*), thus being able to relate it to the color variation (∆E). The samples (Sm, Cu-Sm, Sm/Dye, and Cu-Sm/Dye) were dispersed in white paint at 10% and 20% (% w/w) to evaluate the ability to inhibit different microorganisms. The modification with copper ions promoted an increase in the adsorptive capacity relative to the raw smectite and provided antibacterial and antifungal action to the hybrid pigment against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Candida albicans. The Cu-Sm and Cu-Sm/Dye samples showed excellent results against all studied microorganisms and reveal successful materials that can be used in environments that require microbiological protection.

Compreender as dificuldades apresentadas por estudantes e professores, no processo de ensino e aprendizagem de Química no conteúdo de Estequiometria é de extrema importância e de longa data, devido aos grande entraves matemáticos e de memorização que os estudantes tem de lidar, tornando o conteúdo maçante e desinteressado. Após inicialmente compreender quais as dificuldades dos sujeitos envolvidos, este trabalho propôs o planejamento e desenvolvimento de uma oficina temática e da experimentação  baseada nos trabalhos de Delizoicov e Angotti (1990) e aplicada aos alunos do segundo ano do ensino médio. O desenvolvimento deu-se inicialmente por um questionário como avaliação diagnóstica, seguido de atividades práticas, incluindo a confecção de alfajores e o diálogo final, como processo de validação da aprendizagem. Verificou-se com as atividades em questão, que este tipo de organização contribuiu para o processo de ensino e aprendizagem de forma motivadora, articulando o conhecimento científico ao de senso comum e cotidiano.

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