The local softness 𝑠(𝑟), its derivative [𝜕𝑠(𝑟)/𝜕𝑁] 𝑣 and the global softness S available for atoms, allow for testing the possible sensitivity of atoms/ions in the model conditions available in the alchemical analysis. Calculations have been limited to elements in rows 1 and 2 of the Periodic Table, as the well-recognized variations in electronic properties of atoms in this group allow for critical evaluation of the results. The integrals in eq. 14-18 have been calculated first (Table ). In Table . the calculated parameters of the parabolic functions of ΔZ (A and B in eq. 19-21) have been collected.