Fire Writing (Creative Chemistry Experiments)

You will need:

1. Potassium nitrate
   (available in stores, also
   known as saltpeter)
2. Paper (a heavy paper,
   like parchment or card
   paper)
3. Water
4. Paintbrush
5. Matchstick
6. Candle

You have already tried writing messages in invisible ink. Now amaze everyone with fire writing. Burn a message or drawing onto the paper.

INSTRUCTIONS

1. Make a saturated solution of potassium nitrate, by dissolving a tablespoonful of potassium nitrate
   into ½-1 tablespoonful of water.
2. Take your paintbrush and in broad strokes write or draw out your message. Let the solution be absorbed through the paper where you have written your message.
3. Let this dry completely before you proceed. Remember, your message will become completely invisible. So, mark a spot where you had started your message.
4. Once the paper is dry, ask an adult to light a candle and place the flame at the exact spot where you message starts. Be patient; it takes a few minutes for the fire to catch.

RESULT

The potassium nitrate acts as an
oxidizing agent. As a result, when the fire touches it, it begins to burn the paper through and through where your message was written.