Colorful tea ink @melchemistry7035

MEL Chemistry | Colorful tea ink @melchemistry7035 | Uploaded February 2021 | Updated October 2024, 19 hours ago.
Make your own coloring book out of hibiscus, baking soda, and watercolor paper!

Equipment: cup, hibiscus tea, baking soda, watercolor paper, q-tip.

Make a cup of strong hibiscus tea and prepare a saturated baking soda solution. Apply the baking soda solution to a section of watercolor paper and leave the paper to dry overnight. The tea’s color will deepen overnight as well. The next day, dip a q-tip in the tea and start drawing on the prepared paper – part of the drawing will remain red and part of it will turn blue.

Hibiscus tea contains natural dyes called anthocyanins. Anthocyanins’ structure and color depend on whether they are in an acidic or alkaline medium. Hibiscus tea is acidic, which makes the anthocyanins tint the drink red. Baking soda, on the other hand, creates an alkaline environment and thus changes the anthocyanins’ structure. As a result, the tea turns blue.
More fun experiments await you in the MEL Kids subscription!

Warning! Only under adult supervision.

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