How to Make Invisible Ink with Baking Soda
Easy instructions for making non-toxic invisible ink using nothing more than water and baking soda.
[edit] Steps
- Mix equal parts water and baking soda.
- Dab a cotton swab, toothpick, or paintbrush into the mix.
- Write a message onto white paper, using the baking soda solution as 'ink'.
- Allow the ink to dry.
- Read the message. There are two possible ways to read it:
- 1. Hold the paper up to a heat source, such as a light bulb. The baking soda will cause the writing in the paper to turn brown.
- 2. Paint over the paper with purple grape juice. The message will appear in a different color.
[edit] Tips
- Baking soda and grape juice react with each other in an acid-based reaction, producing a color change in the paper.
- The baking soda mixture can also be used more diluted, with one part baking soda to two parts water.
- Grape juice concentrate results in a more visible color change than regular grape juice.
[edit] Warnings
- If you are using the heating method, avoid igniting the paper - don't use a halogen bulb.
[edit] Things You'll Need
- Baking soda
- Paper
- Water
- Light bulb (heat source)
- Paintbrush or swab
- Measuring cup
- Purple grape juice (optional)
