Where did most elements heavier than hydrogen and helium originate?

• A. They were produced by chemical reactions in planetary atmospheres.
• B. They were synthesized in Earth's mantle.
• C. They were formed in the cores of stars through nuclear fusion.
• D. They were created during the Big Bang.

Answer: (C)

Verified step by step guidance

1. Understand that elements heavier than hydrogen and helium are not formed by ordinary chemical reactions, which only rearrange atoms but do not change the nuclei.
2. Recall that the Big Bang primarily produced hydrogen, helium, and trace amounts of lithium, so heavier elements must have a different origin.
3. Learn that nuclear fusion in the cores of stars combines lighter nuclei into heavier elements, releasing energy and creating elements up to iron in the periodic table.
4. Recognize that elements heavier than iron are formed in more energetic processes such as supernova explosions, which occur at the end of a massive star's life cycle.
5. Conclude that most elements heavier than hydrogen and helium originated in the cores of stars through nuclear fusion and subsequent stellar processes.