Hooked on Science: Bloody handprint

Materials

* Goldenrod paper

* Baking soda

* Water

Instructions

STEP 1: Mix one cup of baking soda with 1 cup of warm water. Dip the palm of your hand into the baking soda and water.

STEP 2: Slap your hand on a piece of goldenrod paper and observe.

Explanation

The goldenrod paper turns bright red when slapped with the palm of your hand, which is covered with baking soda and water. Goldenrod paper is made from a dye, which is a pH indicator. Goldenrod paper turns bright red when exposed to a base such as ammonia or baking soda and turns a bright yellow when exposed to an acid such as vinegar or lemon juice.

Jason Lindsey is a science outreach educator with Hooked on Science. Check out his websitehookedonscience.org for webcasts and experiments.