The gas-phase radiolysis of C2N2+ argon mixtures has been used as a means of following CN radical reactions with a number of hydrocarbons. Rate constants for the reaction with ethylene, propylene, 1,3-butadiene and benzene approach the collisional limit and reflect the extremely electrophilic nature of CN radicals. Rate constants for hydrogen abstraction from methane and ethane have also been determined and enable comparisons to be made with halogen atom reactions.