This paper confirms the intermediate N2O(a) pathway to N-2 in the NO reduction on iridium surfaces. The spatial distributions of desorbing product N-2 have been compared with each other in steady-state N2O + CO and NO + CO reactions on Ir(110) by means of angle-resolved desorption. In the former reaction, the N-2 emission is fairly concentrated on the normally directed plane in the [001] direction and split into two-directional ways, being collimated at 46-58 degrees off normal. In the latter reaction, the N-2 desorption consists of a normally directed component and two-directional components. The former component shows remarkable anisotropy; i.e., the distribution is sharp on the normally directed plane in the [001] direction and broad on the plane perpendicular to it. This component originates from the association of adsorbed nitrogen atoms. The other components are collimated at around 54 degrees normal towards the [001]and [001] directions and they come from the decomposition of intermediate N2O(a). The off-normal components significantly share the total N-2 emission below approximately 550 K. At higher temperatures, these become minor and mostly invisible above 650 K. The desorption of counter-product CO2 is normally directed and shows anisotropy in both reactions. (C) 2017 Elsevier B.V. All rights reserved.