Carbon-12

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/carbon-12

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. How heavy is Carbon-12?Defined as exactly 12 atomic mass units (u)
2. What is the abundance?Constitutes 98.93% of terrestrial carbon
3. What is the stellar origin process?Triple-alpha process in stellar cores
4. How does Carbon-12 form in stars?In stars, three helium atoms fuse together in a process called the triple‑alpha reaction, creating Carbon‑12 thanks to a special energy resonance.
5. Why is Carbon-12 used as the standard for atomic mass?Its mass is defined as exactly 12 atomic mass units, giving scientists a fixed point to measure the masses of all other atoms.

Stellar Nucleosynthesis: The process by which elements are created within stars through nuclear fusion reactions.
Atomic Mass Unit (u): A standard unit of mass used to express atomic and molecular weights, defined as 1/12 the mass of a carbon-12 atom.
Isotopic Fractionation: The process by which the relative abundance of isotopes changes due to differences in their physical and chemical properties.