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PurposeAlthough technology is a defining characteristic of distance education, assessment of the applicability of such resources in knowledge dissemination is greatly warranted to ensure effectivity. Hence, the purpose of this study was to assess the viability of a novel tool in teaching practical chemistry online.Design/methodology/approachHere, a resource named “virtual chemistry lab space” (VCLS), which allowed the learners to virtually engage in practical activities, was administered among learners enrolled in a practical chemistry course at the Open University of Sri Lanka and feedback was collected to ascertain the learner perception on the resource.FindingsIn total, 76% of respondents indicated familiarity with the VCLS, while 59% indicated that they were interested in engaging in activities provided through this resource during the pandemic lockdown. Also, 70% indicated that the VCLS was helpful to understand the course content during the pandemic period, while 82% indicated that they are likely to use it in the future.Research limitations/implicationsThe prevalent problems related to using the VCLS were lack of Internet access, physical interactions and time. However, the overall opinion on the VCLS was notably positive, while a majority indicated that flexibility to the learners, access to learning resources and use of technology in education will improve due to the use of this novel tool.Originality/valueOnline course delivery has been greatly restricted to areas of education where distant delivery could be easily adopted while it is seldom found in areas such as practical chemistry. Hence, the study indicates novelty and notable originality within the ODL system.

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Toxic heavy metal pollution of water and soil is a major environmental concern for which conventional remediation approaches do not provide an appropriate solution. Phytoremediation, which involves removal of pollutants from water and soil through plants, is of low cost and environmentally friendly. In this study, the phytoremediation potential of Lemna minor for the uptake of Cr(VI) at the optimum nutrient strength for Cr(VI) uptake was investigated. Capacity assessment for chromium absorption by Lemna minor was carried out for 7 days at different levels of chromium concentrations. The time required for significant absorption of chromium was estimated in a time course experiment by growing Lemna minor in 3 mg/L chromium solution in which the plant showed no toxicity. Plant samples were harvested at 24 hour intervals for 5 days and wet weight was obtained to determine relative growth; the dried samples were analyzed for chromium using Atomic absorption spectrophotometer. Plant growth decreased significantly with increasing concentration of chromium in the nutrient solution and chlorophyll content (greenness) was also affected. Maximum uptake of chromium (5.8 x 10 3 µg/g dw) was at 8 mg/L in ambient solution. However, the bio-concentration factor (BCF) decreased with increasing chromium in the ambient solution. The BCF was 1000 for chromium up to 3 mg/L. In the time course experiment, growth of Lemna minor and chromium accumulation increased significantly with time up to the 3 rd day (3119 µg/g dw). These results suggest that Lemna minor is an extreme accumulator of chromium and could be considered for chromium (VI) removal from waterways.

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