12. The peak of the stability curve occurs at ⁵⁶Fe. Elements up to iron are produced in the cores of massive stars by exothermic fusion reactions. This is the fundamental reason that iron and lighter elements are much more common in the Universe than elements with higher mass numbers. Show that ⁵⁶Fe has a higher binding energy per nucleon than its neighbors ⁵⁵Mn and ⁵⁹Co. Compare your results with Figure 29.4.

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