Teaching Acid-Base Fundamentals and Introducing pH using Butterfly Pea Flower Tea

Area of Science:

• Chemistry
• Education

Background:

• Early engagement in science, technology, engineering, and mathematics (STEM) is crucial for educational development.
• Natural pH indicators offer accessible and safe methods for introducing chemical concepts to young learners.

Purpose of the Study:

• To detail an educational activity using butterfly pea flower (Clitoria ternatea) anthocyanins as a natural pH indicator.
• To assess the effectiveness of this activity in teaching acid-base chemistry to primary and high school students (ages 7-14).

Main Methods:

• Students extracted anthocyanins from Clitoria ternatea using hot water.
• The natural extract was used as a pH indicator to test various household solutions.
• Students observed color changes to determine acidity, basicity, and relative strengths of solutions.

Main Results:

• The butterfly pea flower indicator demonstrated a wide range of colors corresponding to different pH levels.
• Students successfully differentiated between acids and bases and compared their strengths using the indicator.
• Reasoning based on indicator color changes and chemical reactions was commonly observed.

Conclusions:

• The Clitoria ternatea anthocyanin activity effectively introduces fundamental acid-base chemistry concepts.
• This educational approach utilizes non-toxic, readily available materials for hands-on learning.
• The activity supports understanding of pH, acid/base strength, dissolution, neutralization, and qualitative analysis.