Question

Nucleosynthesis is the process in which nuclei fuse together to form different elements. The table summarizes nucleosynthesis in stars.

Life Stage Main Nucleosynthesis Process
main sequence Hydrogen is fused into helium.
giant or supergiant A smaller star fuses helium into carbon and oxygen. A massive star also fuses heavier elements up to iron.
death The core of a smaller star contracts into a white dwarf. A massive star contracts and then explodes into a supernova that creates elements heavier than iron.

What conclusion can be made from the table?
A.
Nucleosynthesis speeds up over time as stars progress through their stages.
B.
Nucleosynthesis creates all elements on the periodic table by the time a star dies.
C.
Nucleosynthesis varies based on the mass and stage of the star.
D.
Nucleosynthesis produces less energy in smaller and younger stars.

Answer 1

C. Nucleosynthesis varies based on the mass and stage of the star.

The table shows different fusion processes occur at different life stages (e.g., hydrogen fusion on the main sequence, helium and heavier-element fusion in giants) and that massive stars produce heavier elements (up to iron and beyond in supernovae) while smaller stars do not.