With the aim of finding out whether the predicted 7s(2)7p(1/2) ground-state electron configuration of Lr will have an effect on its reactivity, calculations of the adsorption properties of Lr(7s(2)7p), its homologue Lu(6s(2)5d), and the related p element TI(6s(2)6p) on the surface of Ta were performed using the relativistic periodic ADF BAND suite. The obtained adsorption energies, E-ads(M), are in excellent agreement with the measured adsorption enthalpies of Lu and Tl, showing that Lr adsorbs on the surface of Ta similarly to Lu and much differently (215 kJ/mol more strongly) from Tl. An AO population analysis reveals that Lr interacts with the Ta surface preferentially via the 7s AO, with some participation of the 6d as well as 7p(1/2) and 7p(3/2) AOs. In contrast, E-ads(Tl) is governed mainly by the 6p(Tl) AOs. Thus, the present investigations show that Lr should behave like Lu but not like the p element Tl on transition-metal surfaces.