It’s Easy Being Green: A Snapshot of a Professional Development Program Focused on Greener Laboratory Options in the Chemistry Classroom through the Lens of a Titrimetric Analysis of Milk of Magnesia and Vinegar

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 25 (2020) pp 184-193

It’s Easy Being Green: A Snapshot of a Professional Development Program Focused on Greener Laboratory Options in the Chemistry Classroom through the Lens of a Titrimetric Analysis of Milk of Magnesia and Vinegar

Maria Danielle Garrett

Department of Chemistry and Physics, Belmont University, 1900 Belmont Boulevard, Nashville, Tennessee 37212, danielle.garrett@belmont.edu
Received July 12, 2020. Accepted August 30, 2020.

Published: 1 December 2020

Abstract. 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.

Key Words: Laboratories and Demonstrations; general chemistry; inservice teacher professional development; chemistry; chemical reactions; acid-base; titrations; laboratory experiments; green labs; physical science; high school; curriculum; NGSS

(*) Corresponding author. (E-mail: danielle.garrett@belmont.edu )

Article in PDF format (852 KB) HTML format

Supporting Materials:

The Supporting Materials include the old state standards (provided to teachers in 2015 for the “Acid-Base Titrations: Unknown Concentrations and Titration Curves” laboratory experiment) as compared to the current state standards. (183 KB)