It’s Easy Being Green

Student and teacher safety, access to laboratory supplies and waste disposal services, and budgets are just a few factors that may impact and influence how much or even if lab experiments and activities are used in the chemistry classroom. “It’s Easy Being Green: Budget-Friendly Safety-Conscious Chemistry Labs for the Secondary Science Classroom of Today” was developed to provide quality, accessible and cost-efficient hands-on chemistry professional development opportunities for middle and high school science teachers. Since 2015, almost 20 laboratory experiments or activities – for all levels of chemistry content – have been developed for this workshop series. One experiment – the titration of milk of magnesia with 5% acetic acid white vinegar, using a red cabbage leaf indicator – is detailed in this paper. Instructions regarding instructor preparation, pre-lab questions, data analysis and post-lab question are included. Results for the concentration of acetic acid in white vinegar (0.93 ± 0.15 M (three trials) and 0.85 ± 0.04 M (treating the first trial as a pilot)) were consistent with the theoretical value (0.833 M). The experimentally determined equivalence point (pH = ~ 7) was also found to be reproducible, using pH data collected both from pH paper and a digital pH meter.