The role of dealloying in the corrosion resistance of MgZn2 has been investigated for the first time. The elemental dissolution kinetics of a synthetic, nominally pure MgZn2 intermetallic compound was investigated and compared with pure Mg and Zn in 30 mM NaCl with pH = 10.1. Atomic emission spectroelectrochemistry was used to monitor Zn and Mg dissolution as a function of time at open circuit, during linear scan polarization, and at various applied potentials. Zn and Mg displayed a mutual inhibitive effect at open circuit which was explained by the formation of Mg depleted Zn / Zn oxide film. Polarization experiments revealed a Type II dealloying mechanism in which Zn and Mg dissolve simultaneously and congruently above the critical potential, E-c, while preferential Mg dissolution dominates below Ec. Preferential Mg dissolution leads to the formation of a Mg depleted metallic Zn layer which suppresses further Mg dissolution. In oxygen saturated electrolyte, O-2 reduction was the major cathodic reaction on Zn but was completely inhibited on Mg. The intense cathodic reduction of O-2 on Zn led to a cathodic dissolution of Zn, probably due to the increased interfacial pH. (c) The Author(s) 2017. Published by ECS. All rights reserved.