Fluorescence Lesson

Fluorescence at a glance

Background

Have you ever seen something that glows in the dark or changes color under a black light? That’s fluorescence at work! Fluorescence is a special ability that some materials have to absorb invisible light (like UV light) and then emit visible light, creating bright, colorful effects.

In this lesson, students will explore the amazing world of fluorescence, discovering how certain materials can glow with vivid colors when exposed to invisible light. By learning about the science behind fluorescence, students will see how everyday objects can have hidden, colorful properties.

Lesson Objective

Students will explore the phenomenon of fluorescence by examining how certain glass pieces emit visible light when exposed to ultraviolet (UV) light. They will learn about the role of rare earth elements in creating this glowing effect.

Experiment Description

Using a small UV light, students will observe two pieces of nearly colorless glass in both normal and darkened conditions. Under the UV light, they will see the glass emit vivid colors, demonstrating the fluorescent properties of the material.

Materials List

Two pieces of transparent, nearly colorless glass
Small UV light
Darkened room or space

Safety Precautions

Avoid direct exposure of the UV light to skin and eyes. Always turn off the UV light when not in use and handle the glass pieces with care.

The Experiment

Fluorescence is a special effect where certain materials can give off visible light after absorbing invisible light, like ultraviolet (UV) light. Imagine you have two pieces of glass that look clear and colorless under normal light. But when you shine UV light on them, they start to glow in bright colors. This happens because the glass contains special elements called rare earth elements, which can absorb the UV light and then emit visible light in different colors.

In this experiment, you will use a small UV light to see how fluorescence works in glass. First, look at the two pieces of glass under normal light and note how they look. Then, turn off the lights and shine the UV light on the glass pieces in the darkened room. You will see that the glass starts to glow with bright colors. This is because the rare earth elements in the glass are absorbing the UV light and then re-emitting it as visible light.