The proton–proton cycle thought to occur in the sun consists of the following sequence of reactions:

(1)

(2)

(3)

In these reactions  is a positron (mass = 0.000 549 u), n is a neutrino (mass ≈ 0 u), and g is a gamma ray photon (mass = 0 u). Note that reaction (3) uses two  nuclei, which are formed by two reactions of type (1) and two reactions of type (2). Verify that the proton–proton cycle generates about 25 MeV of energy. The atomic masses are  (1.007 825 u),  (2.014 102 u),  (3.016 030 u), and  (4.002 603 u). Be sure to account for the fact that there are two electrons in two hydrogen atoms, whereas there is one electron in a single deuterium () atom. The mass of one electron is 0.000 549 u.

Transcribed Image Text:

H + |H → }H + ſe + v H + }H – He + He He + y He + H + H