The dissociative adsorption and recombination of CO, N 2, SO, and O 2 on Ni(111) has been studied by LEED, AES and TPD. The kinetic parameters were determined for O + O, N + N, S + O, C carbide + O recombination. All four reactions displayed second order kinetics with pre-exponential factors of 10 −2 ± 1 cm 2 atom·s . The activation energies were E o+o = 440 kJ mol , E N + N = 210 kJ mol , E s+o = 310 kJ mol and E c carbide+o = 175 kJ mol . The kinetics of the C graphite + O recombination were found to be first order indicating a condensed graphite phase with reaction at the phase boundary. These kinetics were further complicated due to an apparent phase transition of the adsorbed graphite at 970 K. The TPD results were used to estimate heats of adsorption. These estimates correlated with the heats of formation of bulk compounds.