Neptunium-237 has a Atomic mass of 237 g/mol. The reaction of decay is shown as, ²³⁷₉₃Np ---------> ᵇₐX + ⁴₂He where, X = Unknown Element ᵇ = Atomic Mass of Unknown Element ᵃ = Atomic number of Unknown Element Solving for ᵇ, 237 = ᵇ + 4 ᵇ = 237 - 4 ᵇ = 233 Solving for ₐ , 93 = ₐ + 2 ₐ = 93 - 2 ₐ = 91 Now, Putting values in ᵇ and ₐ of X,
²³³₉₁X
Searching Periodic table for atomic number 91.
²³³₉₁Pa
Result: The child Isotope is Protactinium (Pa) having atomic number 91 and Atomic mass 233 g/mol
