As a star's evolution approaches the Type II supernova, we find:
A)the heavier the element, the less time it takes to make it.
B)the heavier the element, the higher the temperature to fuse it.
C)helium to carbon fusion takes at least 100 million K to start.
D)photodisintegration of iron nuclei begins at 10 billion K to ignite the supernova.
E)All of the above are correct.

Question

Quizplus · Accepted Answer

All of the statements are correct. As a star evolves towards a Type II supernova, it fuses lighter elements into heavier ones, which requires higher temperatures. Helium fusion into carbon requires at least 100 million K to start. As the star runs out of lighter elements to fuse, it begins to fuse heavier elements, such as iron. However, the fusion of iron actually requires energy instead of releasing it, which causes the star to collapse and ignite a supernova. At 10 billion K, photodisintegration of iron nuclei begins, further contributing to the collapse of the star.

As a Star's Evolution Approaches the Type II Supernova, We