The chemisorption of N-2 on Ru(001) has been studied using supersonic molecular beam techniques. The initial molecular chemisorption probability, S-0, was measured as a function of incident energy, E(i), from 0.021 to 0.90 eV and angle of incidence, theta, from 0 degrees to 60 degrees at a surface temperature of 77 K. At a normal angle of incidence, the value of S-0 decreases with increasing kinetic energy in the low and intermediate energy regimes and is constant in a higher energy (0.4 eV < E(i) < 0.7 eV) regime. As the angle of incidence increases, the value of S-0 decreases more rapidly with E(i) at low energies. At theta = 60 degrees, S-0 decreases with increasing kinetic energy, passes through a local minimum near E(i) = 0.2 eV, and then increases to the same constant value as in the normal incidence case. At E(i) = 0.90 eV : the most energetic beam used in this study, the value of S-0 decreases slightly from this constant value. Similar measured trends in the angular and energy dependence, particularly at intermediate energies, have not been reported previously for a molecular chemisorption system, and we qualitatively describe this behavior by combining a trapping-mediated mechanism (dominant at low incident energies) and a direct molecular chemisorption mechanism (dominant at high incident energies). We also report measurements of the initial dissociative chemisorption probability of N-2 on Ru(001) and conclude that this probability at E(i) = 1.25 eV and normal incidence does not exceed 1 x 10(-3) at a surface temperature of 600 K.