Question

Cosmologists modeling the origin of the elements postulate nuclides with very short half-lives. One of these nuclides,${}^{\mathbf{8}}\mathbf{Be}\left(t_{1/2}=7\times {10}^{-17}s\right)$, plays a key role in stellar nucleosynthesis (p. 1099) because it must fuse with${}^{\mathbf{4}}\mathbf{He}$to form${}^{\mathbf{12}}\mathbf{C}$before decaying. Another explanation involves the simultaneous fusion of three${}^{\mathbf{4}}\mathbf{He}$nuclei to form ${}^{\mathbf{12}}\mathbf{C}$. Comment on the validity of this alternative mechanism.

Short answer

The bimolecular mechanism is more likely than three He nuclei fusing.

Step-by-step solution

Definition of Concept

Nuclear reaction: A nuclear reaction occurs when a lighter nucleus fuses together to form new stable nuclei, or when a heavier nucleus splits into stable daughter nuclei, releasing a large amount of energy.

Comment on the validity of this alternative mechanism