Create invisible ink with lemon juice! It is a lot of fun, and you can pretend you are a secret agent as you keep all your secret codes and messages hidden from others. All you need is some basic household objects and the hidden power of lemon juice!
Supplies: Lemon juice, Q-tip, candle.
Step 1: Write a secret message with the Q-tip and lemon juice.
Step 2: Slowly wave the paper over the candle. This step took a few ttys to get the hang of it, but once you do its really fun. The lemon juice browns faster than the paper, so the letters seem to appear magically. Be careful to not start a fire!
Lemon juice is an organic substance that oxidizes and turns brown when heated. Diluting the lemon juice in water makes it very hard to notice when you apply it the paper, no one will be aware of its presence until it is heated and the secret message is revealed. Other substances which work in the same way include orange juice, honey, milk, onion juice, vinegar and wine!