The Science of Glow: What Happens When You Add Lemon Juice to Highlighter Ink?

When you highlight something, the ink glows because it contains fluorescent molecules with electrons that can absorb energy from light. These electrons jump to higher energy levels when exposed to light and then fall back down, releasing that energy as visible light… that’s the bright glow you see. The ability to do this comes from a stable arrangement of bonds in the molecule, called a chromophore.

When you add lemon juice, the citric acid releases hydrogen ions that interact with the dye’s chromophore, changing its structure. This disruption prevents electrons from making those energy jumps and transitions, so the molecule can no longer absorb or release light in the same way, and the glow disappears.

#science #physics #learning #facts #chemistry

credits:
Anupriya Sharma
Rishi Kumar