🧪 Science hiding in magic

The science, trick by trick

• Pepper Scatter: Water has surface tension: the top layer behaves like a stretchy skin, and the pepper is light enough to sit on it.
• The Arrow Flip: Light bends when it crosses from water into glass into air.
• The Water Vanish: This is called total internal reflection.
• The Glowing Potion: Quinine soaks up ultraviolet light, which human eyes can't see, and hands it straight back out as visible blue light.
• Secret Message Ink: Grape juice has a natural dye in it that changes colour depending on what it touches.
• The Upside-Down Water Card: The air around us presses on everything, quite hard, from every direction.
• The Balloon Static Wand: Rubbing the balloon on your hair scrapes tiny electric charges off it, and the balloon keeps them.
• The Colour-Changing Potion: Grape juice and red cabbage contain a dye that changes colour depending on what it is mixed with.
• The Obedient Egg: Whether something floats depends on how heavy it is compared with the water it pushes out of the way.
• The Floating Paperclip: Water molecules pull on each other, and at the top there is nothing above them to pull back, so the surface pulls itself tight into something like a skin.
• The Hole in Your Hand: Your eyes are a few centimetres apart, so they never see quite the same thing, and your brain normally blends the two pictures into one.
• The Loop of Mystery: A loop with a half twist in it is a Möbius band, and it only has one side and one edge: run a finger along it and you come back to where you started having covered what looks like both faces.

The rules of the Potion Lab

Everything in the Potion Lab is food-safe, or a dry tool like a marker that never touches the liquid, and the shop checks that in its code. A potion is always for looking at, never for drinking, and the trick pages say so out loud.

One trick needs a small ultraviolet torch, and a grown-up always holds it and never shines it at anybody's eyes. One uses a balloon, which a grown-up blows up.

Turning a trick into an experiment

After the gasp, ask a question: what if we used salt instead of soap? Warm water instead of cold? A square glass? Children who change one thing and watch what happens are doing exactly what scientists do.

The kitchen-science Top 10 ranks these easiest first, and the science magic tricks page has all of them in one table.