23. Why does hydrogen fusion give off energy? Where does this energy
come from? What are the product nuclei?
24. Where does most of the synthesis of helium and heavier elements
25. How are Li, Be, B, and C made during natural synthesis? How
does your answer explain the rarity of the first three in the universe,
and the relative abundance of carbon?
26. By what reactions are the elements from oxygen to silicon formed?
How are the heavier elements to iron formed? What role does temperature
play in determining how far this process will go?
27. Why does this elemental synthesis process stop at iron? What
happens when iron and other nuclei fuse to make even heavier elements?
28. Are all the elements between carbon and iron formed by the reactions
you outlined in response to Question 26? If not, what types of elements
are systematically omitted from this scheme? How are they formed?