Practice free →
HomeAlberta Diploma ExamsPhysicsThe Atom › In the sun's proton-proton cycle, what is the ov…

In the sun's proton-proton cycle, what is the overall result of fusing hydrogen nuclei together?

AHelium nuclei split apart into individual protons
BHydrogen nuclei absorb energy and cool the sun's core
CHydrogen nuclei combine to form helium-4, releasing energy
DIron nuclei are converted directly into hydrogen
Answer & Solution
Correct answer: C. Hydrogen nuclei combine to form helium-4, releasing energy
1. The proton-proton cycle is the principal sequence of fusion reactions inside the sun. 2. It fuses hydrogen nuclei, the sun's most abundant nuclide, into helium-4 nuclei, releasing energy in the process. 3. This is the opposite of helium splitting into protons, which would be a fission-like process, not fusion. 4. The reaction releases energy rather than absorbing it, and no iron is involved in this cycle at all. 5. So hydrogen fusing into helium-4 while releasing energy is correct. _Source: OpenStax Physics (CC BY 4.0), Ch 22 "The Atom", section 22.4 Nuclear Fission and Fusion_
Solve this in the app — Alberta Diploma Exams practice & 24k+ MCQs →
Related questions