Background

Background Video

This experiment can be implemented by demonstrating to students that even though Ultraviolet rays are not visible to the naked eye, they are very much present and cause damage to the body. The UV beads demonstrate the presence of the UV rays found in the sun. These UV rays travel as wavelengths from the sun to Earth. The light induces chemical reactions to occur causing color change in the pigmented beads.

PK-3 grade

At this grade level, students understand that the sun gives off a type of ray called Ultraviolet rays also called UV rays. At this grade level, students know substances change when they are mixed, cooled or heated. Students know energy travels from one place to another by waves like water waves, sound waves, and electric current. Students know energy comes from the sun and travels to the earth in the form of light. They will know all matter is made of small particles called atoms that cannot be seen by the naked eye. These rays are invisible but you can see the colors they produce on the bracelets. The objects are seen when light traveling from objects to our eyes. Indoors the bracelets are white however, when you take them outside in the sun, the UV rays change their white coloring into different bright colors. These invisible rays are harmful to your eyes and skin. This experiment shows the harmful effects of Ultraviolet rays and how fast they work.

4-6 grade

At this grade level, students understand that light from the sun travels through space and to the Earth. This sun light contains harmful Ultraviolet rays. Light can be absorbed and reflected by objects allowing our eyes to see specific colors. Solar energy reaches Earth through radiation, mostly in the form of visible light. When colors are reflected off on object they enter our eyes and this determines the colors we see. The UV rays cause a chemical reaction in the coloration of the bracelets which cause them to change from white to a vibrant color. Exposure to UV rays is harmful, and the beads can show how fast the UV rays affect them when exposed. An example of this reaction is also expressed in photochromic lenses also known as transition glasses that are light sensitive eyeglass lenses that change to a darker film in the bright sunlight and become clear indoors.

Middle school

At this grade level, students understand that Ultraviolet rays from the sun are electromagnetic radiation and consist of shorter wavelength which can ionize atoms and cause damage to living cells. All electromagnetic radiation travels through a vacuum at the same speed, called the speed of light. The exposure to UV rays on the bead bracelet cause a chemical reaction of the pigment leading to a color change from white to vibrant colors. We are able to see these colors by the light refracting, reflecting, transmitting or absorbed by matter.

College level

At this level, students are knowledgeable that Ultraviolet rays are electromagnetic radiation just beyond what our eye can see on the violet side of the rainbow. The sun is our main source of UV coming in as a cosmic force. UV has the power to ionize electrons in molecules like DNA and cause damage. UV is invisible to the naked eye but can cause objects to go through a color changing reaction. The different colored beads each contain a different organic molecule that is colored in one form but that can undergo a chemical reaction to form a colorless compound. When the UV beads are exposed to the sunlight this causes a chemical reaction leading to a color change. Ultraviolet light has significant energy which is transferred to the colorless compound which causes the molecule to react to form the colored form. After light is removed, the colored compound reacts back to form the colorless form with heat favoring that reaction.  This is photochromism or the ability of a material to change color on exposure to light. The main message is that light is a form of energy which cause chemical reactions to occur. This color changing bead reaction proves that UV rays are present in the light emitted from the solar source. In this case, the reaction causes a color change to a colored pigment.