Photodegradation

High school (ages 12+)
Environment & Earth

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/photodegradation

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the primary energy input?Photons, particularly in the ultraviolet (UV) and visible light spectrums
2. What is the key molecular processes?Photo-oxidation, photo-hydrolysis, free radical formation, bond cleavage
3. Why does sunlight fade old paintings and books?Sunlight gives energy to pigments and fibers, making them react with oxygen or water, which fades colors and makes materials brittle.
4. How do scientists protect museum treasures from light damage?Museums use lights with little UV, put UV‑filtering films over displays, and keep the air dry and low in oxygen to slow the breaking of the objects.

Chromophore: A part of a molecule responsible for absorbing specific wavelengths of light.
Photo-oxidation: Material degradation initiated by light in the presence of oxygen.
Free Radicals: Highly reactive molecules with unpaired electrons, often formed during photodegradation.