Goldenrod Bleeding Paper

Paper That Bleeds Red Blood

Goldenrod paper is a special paper containing dyes that react to pH change.
Goldenrod paper is a special paper containing dyes that react to pH change. A basic pH makes the paper appear to bleed. Paul Taylor, Getty Images

This special paper drips blood! If you prefer, you can write a bloody secret message or create a bloody hand print. The paper contains a pH indicator that turns red in the presence of a base.

Bleeding Paper Materials

This project uses a special paper, called color-changing goldenrod paper. It is available at Amazon and some education and craft stores. Be sure to use the color change goldenrod paper and not just any yellowish paper.

The color change results from alkaline conditions, which can be obtained using ammonia, baking soda, laundry detergent, washing soda, or soapy water. Ammonia mixed with water works extremely well, but younger researchers may wish to use baking soda in water, since it is very safe.

  • color-changing goldenrod paper
  • household ammonia or baking soda
  • cotton swabs or cotton balls
  • wax crayon or white candle

Bloody Hand Print

  1. Dip your hand in a mixture of household ammonia and water or baking soda and water.

     

  2. Slap your hand onto a sheet of goldenrod paper. See the bloody hand print? If your hand was wet enough, the paper will appear to bleed, too.

Bloody Hidden Message

  1. Use a wax crayon or piece of white candle to write a message on the goldenrod paper. The message should appear invisible on the paper.

     

  2. Reveal the message (in 'blood') by wiping the paper with a cotton ball dipped in ammonia.

How It Works

Goldenrod paper contains a pH indicator that changes the paper from golden to red in the presence of a base, such as ammonia.

Notice the red color fades after a while. This is because carbon dioxide in the air makes the liquid more acidic. You can play with stronger bases, such as washing soda, which will not change color in air. For a stronger base, you can counteract the pH using a common household acid, such as lemon juice or vinegar.

More Projects To Try

Bleeding Knife Chemistry Trick
Halloween Color Change Reaction
Make Red Cabbage pH Indicator