What is thought to be the physical mechanism that was responsible for the present mix of chemical elements in the universe?
A) All the known elements have been formed by the breakup (radioactivity) of the heavy elements formed in the initial Big Bang.
B) All the known elements were formed in the Big Bang.
C) Hydrogen and helium were formed in the Big Bang, whereas the heavier elements have been slowly forming by collisions in cold interstellar gas clouds.
D) Hydrogen and helium were formed in the Big Bang, whereas the heavier elements were made in the centers of stars.

Question

Quizplus · Accepted Answer

Hydrogen and helium were indeed formed in the Big Bang, but the heavier elements (from lithium onwards) have been synthesized in the cores of stars through nuclear fusion processes. This stellar nucleosynthesis is responsible for creating most of the elements found in the universe today.

What Is Thought to Be the Physical Mechanism That Was