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Title: Teaching Acid–Base Fundamentals and Introducing pH Using Butterfly Pea Flower Tea
Stimulating interest in science at an early age is important for STEM education. This work details an educational activity utilizing the anthocyanins found in the butterfly pea flower (Clitoria ternatea). This activity was developed for use in official classroom settings, online, and/or at-home with parental or educator guidance. Primary and high school students aged 7 to 14 performed a straightforward extraction of anthocyanin pH indicators from Clitoria ternatea with hot water. Students were able to use this indicator and its vast range of colors to compare the acidity and basicity of different household solutions. Most responses recorded show that students used reasoning from the indicator and a subsequent chemical reaction to correctly differentiate acids from bases and compare their strengths. Overall, this activity's application of non-toxic and easily accessible indicators from the butterfly pea flower assisted in introducing young students to various concepts in acid-base chemistry, including acid/base strength and pH, solute dissolution, neutralization reactions, and qualitative analysis.  more » « less
Award ID(s):
2304955
PAR ID:
10511406
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Chemical Society and PubMed Central
Date Published:
Journal Name:
Journal of Chemical Education
Volume:
101
Issue:
3
ISSN:
0021-9584
Page Range / eLocation ID:
1373 to 1378
Subject(s) / Keyword(s):
Acids Bases Elementary Hands-On Learning High School Informal Learning Introductory Chemistry Manipulatives Middle School Science Outreach Public Understanding pH.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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