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A plethora of literature has reported that hands-on and minds-on practical activities are central during teaching and learning processes. Yet, it appears that such activities are not enacted in most Namibian rural schools. Arguably, reason most cited amongst many teachers is that there is a lack of resources to do practical activities, especially in under-resourced rural schools. It is against this backdrop that the purpose of this study was to explore the use of easily accessible resources in carrying out hands-on and minds-on practical activities with a view to reduce reluctance or increase self-efficacy and motivation by science teachers to include these in science lessons. A case study approach underpinned by an interpretive paradigm was adopted. The study was conducted with 21 in-service science teachers from mostly rural schools in Namibia who were all on a two-year part-time BEd (Honours) programme delivered by a South African university in the Eastern Cape. Workshop discussions, worksheets and mind maps, observations, semi-structured interviews and teacher reflections were used to generate data. Vygotsky’s socio-cultural theory was used as a theoretical framework to analyse the qualitative data generated. The findings of the study revealed that for teachers to use easily accessible resources to carry out hands-on and minds-on practical activities in their science classrooms, they need the knowledge and exposure on how to use these resources. The findings thus showed that this interventionist study raised motivation, knowledge and the skills of the science teacher participants to include practical activities in their science lessons, using easily accessible resources in particular. The implication is that if teachers are afforded opportunities, through professional learning communities, to themselves engage in hands-on and minds-on practical activities using easily accessible resources, they can be enabled and motivated to enact these in their science classrooms. more...

Chemical equilibrium is one of the most important yet difficult topics to teach. The purpose of this study was to examine how two science teachers experienced the mediation of and how they mediated... more...

Pharmaceutical chemistry, medicinal chemistry and the drug discovery process require experienced practitioners to employ reasoned speculation in generating creative ideas, which can be used to evolve promising molecules into drugs. The ever-evolving world of pharmaceutical chemistry requires university curricula that prepare graduates for their role as designers with the capability of applying complex concepts in pharmaceutical chemistry, thereby improving the decision-making process. Common methods of teaching drug discovery, including the linear nature of the traditional case study model, do not provide a realistic picture of the underlying complexity of the process, nor do they equip students with the appropriate tools for personal sense making and abstraction. In this work, we discuss the creation of an open-ended, nonlinear case study for 3rd year pharmaceutical chemistry students, developed from drug discovery research conducted at Rhodes University. Furthermore, we discuss blending problem based learning (PBL) with peer-led team learning (PLTL) in the context of curriculum transformation, underpinned by the theory of semantic waves, to assist students in the early attainment of abstract concepts and answer questions of contextualisation, personal sense making, relatability, relevance and ultimately the skills for lifelong learning. more...

This paper describes a service-learning course in Chemistry Honours at Rhodes University in South Africa. Students visit two schools in different settings, where they present a lecture-demonstration, entitled ‘A Pollutant's Tale’, and two hands-on experiments to school learners. The students are assessed on their learnings as seen through their own reflections on the activities in reflective journals. The reflections from 27 students over four years of the course were analysed to investigate to what extent the educational goals of the course were being met. Six broad themes emerged from student reflections: (1) social awareness; (2) civic responsibility; (3) challenging beliefs; (4) enhanced understanding of science communication and demonstration skills; (5) personal growth; and, (6) evaluating the service-learning experience. In our discussion of these themes, we suggest that through service-learning, students have learnt to do things differently in Chemistry: they have learnt about society beyond the laboratory and beyond their previous life-experiences. Importantly, the students have undergone personal development and picked up critical skills which they will need when traversing life and its challenges – such as, working with and learning from diverse groups of people, teamwork and learning to cope in stressful situations. The paper will be of particular interest to those who are involved in chemistry teaching in both schools and higher education institutions, as well as those interested in service-learning as a pedagogical tool, community and civic engagement and the development of transferable skills in chemistry students. more...

The Khanya Maths and Science Club (KMSC) is an afterschool science/maths enrichment programme for learners in Grades 7–12 supported by postgraduate students and academic staff volunteers. This research seeks to explore the relationship between participating learners’ attitude toward learning science and the characteristics of this afterschool science club. The study draws from Wenger’s community of practice model to explore the features. Six learners participating in the KMSC were interviewed and their journal entries were analysed inductively, resulting in three themes. The study revealed that learners’ attitudes towards learning science were associated with the club’s instructional characteristics, facilitators/environmental characteristics and the level to which science was connected with everyday life. These characteristics are also related to the community of practice elements. It was concluded that incorporating the community of practice model in structuring afterschool science activities could have... more...

Science Expos are intended to develop and empower learners to identify local problems and hence find solutions thereof using scientific processes. Science Expos are perceived as spaces for sharing experiences of science which engender love for science so that learners may ultimately pursue science-related careers. Despite these ideals, there is still poor participation in Science Expos by teachers and learners alike, especially from historically disadvantaged schools in South Africa. A qualitative case study underpinned by a community of practice theory was conducted in four disadvantaged schools in the Eastern Cape, South Africa. The purpose of the study was to understand stakeholders’ perceptions of participation in Science Expos. The data were generated using individual semi-structured interviews with two Expo organisers, three teachers and five learners from disadvantaged schools. Additionally, two focus group interviews were conducted with learners. The data were analysed inductively. The findings of... more...

Given the emphasis on community engagement in higher education, academic departments need to become more involved in the community. This paper discusses a number of outreach activities undertaken by the chemistry department at Rhodes University, South Africa. The activities range from service learning to community engagement with teachers and school students in partnership with other interested parties. Teachers who attended workshops reported that their subject knowledge and confidence had increased and they were subsequently doing more practical work in lessons. Practical chemistry demonstrations and workshops afforded opportunities for school students to observe or perform chemical experiments and interact with university students. Undergraduate students directly benefitted from involvement in community engagement through the development and implementation of credit-bearing service learning. more...

Education institutions globally are increasingly expected to explore avenues for the implementation of service-learning into their curricula. A second-year undergraduate organic chemistry laboratory experiment, in which the undergraduate students make azo dyes, can provide a vehicle for a service-learning module in which university undergraduate students then teach students from resource-limited secondary schools how to make azo dyes. Evidence is provided to show how the theory is reinforced for both sets of students through a shared practical experience. The practical application of chemistry is conveyed through the use of the synthetic azo dyes to dye t-shirts. The results of this study show that the service-learning experience clearly assists undergraduate students to appreciate the role of chemists in the broader society while at the same time increasing awareness of the inequalities in school education systems. more...

A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at second-year level with practical projects in which student teams formulate and prepare relatively simple chemical products for marketing, followed a year later by a more advanced study of the feasibility of producing and marketing a fine chemical on a commercial scale. more...

The influence of substituents and structure on the 13C NMR spectra of four series of benzoxathiepine derivatives has been investigated. Signal assignments in the 13C NMR spectra have been facilitated by the use of several predictive methods, permitting comparison of their relative efficacy. more...

All kinetic analyses aim to determine a sufficient number of kinetic parameters, usually at least an apparent Arrhenius activation energy and pre-exponential factor, and a conversion function or kinetic model (making up a ‘kinetic triplet’), so that accurate extrapolations of kinetic behaviour can be made. “Model-free” methods of kinetic analysis postpone the problem of identifying a suitable kinetic model until an estimate of the activation energy has been made. A major reason for doing this is that misidentification of the kinetic model has a marked effect on the values obtained for the Arrhenius parameters in both isothermal and non-isothermal kinetic analyses. Some aspects of this problem are discussed. The non-parametric kinetics (NPK) method [1] , [2] is a “model-free” method of kinetic analysis that does not seem to have received the attention that it deserves. This is probably because of its mathematical sophistication and the fact that the matrix and non-linear regression calculations involved are not readily automated. The principle of the method appears to be that of “forcing” a set of non-isothermal data into the set which should have been obtained if the experiments had been carried out isothermally. The method deserves wider testing and also raises some interesting aspects of the philosophy behind non-isothermal kinetic analysis. more...

1H NMR spectroscopy, single crystal X-ray analysis and computer modelling have been used to explore the conformational preferences in five series of 1,5-benzodioxepine and 1,5- and 4,1-benzoxathiepine derivatives. more...

In many parts of the world, alkanols are being added to motor fuels to extend fossil fuels. Alkanols are also being added to motor fuels to cut pollution and reduce emission of greenhouse gases. The tie line and liquid-liquid equilibrium data are presented for mixtures of an alkanol + hept-1-ene + water at 25 C. The data are compared to the related mixtures of an alkanol + heptene + water at 25 C. The alkanol refers to all the C[sub 1], C[sub 2], C[sub 3], and C[sub 4] alcohols. The measurements have a bearing on the water contamination problem inherent in gasoline + alcohol blends. more...

Three-component phase diagrams including tie-lines have been determined at the temperature 298.15 K for {methanol or ethanol or propan-1-ol or propan-2-ol or butan-1-ol or butan-2-ol or 2-methylpropan-1-ol or 2-methylpropan-2-ol + (hept-1-yne + water)}. The results are compared with previously reported results on (an alkanol + heptane + water). The conclusions have a bearing on the water-contamination problem inherent in (petrol + alkanol) blends because petrol does contain unsaturated hydrocarbons and the solubility properties of hept-1-yne in this context are similar to those of petrol. more...

The phase equilibria and tie-lines are presented for mixtures of ethylether + water + an alcohol at 25°C. The alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, iso-butanol and tert-butanol. more...

A Ni(II)-dimethylglyoxime ion-imprinted polymer {Ni(II)-DMG IIP} was synthesised by the bulk polymerisation method. The morphology of the Ni(II)-DMG IIP and non-imprinted polymer were observed by scanning electron microscopy and the chemical structures were evaluated by infrared spectroscopy. Selectivity of the Ni(II)-DMG IIP was studied by analysing, using an inductively coupled plasma-optical emission spectrometer, for Ni(II) ions that were spiked with varying concentrations of Co(II), Cu(II), Zn(II), Pd(II), Fe(II), Ca(II), Mg(II), Na(I) and K(I) in aqueous samples. The studies revealed Ni(II) recoveries ranging from 93 to 100% in aqueous solutions with minimal interference from competing ions. Enrichment factors ranged from 2 to 18 with a binding capacity of 120 µg·g-1. Co(II) was the only ion found to slightly interfere with the determination of Ni(II). Selectivity studies confirmed that the Ni(II)-DMG IIP had very good selectivity, characterised by %RSD of less than 5%. The limits of detection and quantification were 3x10-4 µg·mℓ-1 and 9x10-4 µg·mℓ-1, respectively. The accuracy of the method was validated by analysing a custom solution of certified reference material (SEP-3) and the concentration of Ni(II) obtained was in close agreement with the certified one. The Ni(II)-DMG IIP was successfully employed to trap Ni(II) ions from a matrix of sea, river and sewage water. It is believed that the Ni(II)-DMG IIP has potential to be used as sorbent material for pre-concentration of Ni(II) ions from aqueous solutions by solid-phase extraction. more...