Chapter 42 - Nuclear Physics - Exercises and Problems - Page 1274: 1

(a) $^3He$ has 2 protons $^3He$ has 1 neutron (b) $^{32}P$ has 15 protons $^{32}P$ has 17 neutrons (c) $^{32}S$ has 16 protons $^{32}S$ has 16 neutrons (d) $^{238}U$ has 92 protons $^{238}U$ has 146 neutrons

(a) $^3He$ has atomic number 2 $^3He$ has 2 protons Note that $3-2 = 1$ $^3He$ has 1 neutron (b) $^{32}P$ has atomic number 15 $^{32}P$ has 15 protons Note that $32-15 = 17$ $^{32}P$ has 17 neutrons (c) $^{32}S$ has atomic number 16 $^{32}S$ has 16 protons Note that $32-16 = 16$ $^{32}S$ has 16 neutrons (d) $^{238}U$ has atomic number 92 $^{238}U$ has 92 protons Note that $238-92 = 146$ $^{238}U$ has 146 neutrons