How to Make a Secret Message With Baking Soda

This Instructable will show you how to create, and expose secret messages using water and baking soda!

For this fun activity you'll need the following supplies:

1. Baking Soda
2. Printer paper
3. Water (in a cup)
4. Candle
5. Lighter
6. Paint Brush

Pour about a half cup of water into a cup. With the water at room temperature add a teaspoon of baking soda and stir. If all the baking soda dissolves, add another teaspoon of baking soda until there is a thin amount of baking soda settled on the bottom of the cup. Now you know your solution is super-saturated (yes, that's a technical term;) )

Using a paint brush, paint any picture or text you'll like to be your "secret message". Paint with a liberal amount of the solution so that you can see the message in wet solution. Once the message is dry, allow it to dry for 15 about minutes. once it dries the paper will look like a normal, unused sheet of paper.

To reveal the message, expose the paper to a lit candle. Move the paper back-and-forth slowly to heat up the paper. The parts of the paper with the message will show dark coloration. Be careful not to hold the paper in one place over the candle or the paper will catch fire. Do this step near a sink just in-case it catches fire. If the paper catches, toss it in the sink and run water over it.

Your government would be proud! Write large and clearly, and get plenty of practice in. It took me and my kids several tries and several kitchen fires to get this working right! Have fun!