Dry-ice blasting

High school (ages 12+)
Science & Technology

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/dry-ice-blasting

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 cleaning medium?Solid carbon dioxide (CO2) pellets
2. What is the dual cleaning mechanism?Thermal shock from extreme cold and kinetic energy from high-velocity impact
3. How does dry-ice blasting clean surfaces?When the cold pellets hit a surface, they make the dirt contract and become brittle. The fast air stream then pushes the weakened dirt away, and the dry ice turns into gas, leaving the surface clean.
4. Why does dry ice not turn into liquid when it melts?At normal pressure, dry ice skips the liquid stage and goes straight from solid to gas. This is called sublimation and happens because its melting point is below the temperature of the air around it.

Sublimation: The direct phase transition of a substance from solid to gas without passing through the liquid phase.
Thermal Shock: The stress induced in a material by rapid temperature changes, causing contraction or expansion.
Kinetic Energy: The energy an object possesses due to its motion, proportional to its mass and the square of its velocity.
Secondary Waste: Waste generated from the cleaning process itself, such as spent blasting media.