The temperature and concentration dependences of Pb-207 NMR chemical shifts of Pb(NO3)(2) in D2O are reported. The results are analyzed in terms of exchange between a solvated lead ion and the Pb(NO3)(+) contact-ion pair. Predictions of the chemical shift difference between the aquated ion and contact-ion pair are carried out for the gas-phase entities and for the solvated species with a DFT calculation. Previously reported data on Pb-207 NMR chemical shifts of Pb(NO3)(2) in H2O are reevaluated. From the analysis, the enthalpy of dissociation of the contact-ion pair is found to be-42.3 +/- 1.0 kJ/mol.