Tonic Water Glows
Tonic water glows blue.
Teaching & key ideas
What you do: Illuminate both in dim area.
What students see: Tonic water glows blue.
Why it works: Quinine absorbs UV and re-emits visible blue light almost immediately.
Question to ask: Why does the glow stop when the UV light stops?
Lesson flow
Predict → demonstrate → observe → briefly explain → ask: Why does the glow stop when the UV light stops?