A method for activating chemical reactions using non-thermal capillary discharge plasma (NT-CDP) unit or a non-thermal slot discharge plasma (NT-SPD) unit (collectively referred to as "NT-CDP/SDP"). The NT-CDP/SDP unit includes a first electrode disposed between two dielectric layers (8 and 9), wherein the first electrode and dielectric layers having at least one opening (e.g., capillary or a slot) defined therethrough. A dielectric sleeve (3) inserted into the opening, and at least one second electrode (2) (e.g., in the shape of a pin, ring, metal wire, or tapered metal blade) is disposed in fluid communication with an associated opening. A non-thermal plasma discharge is emitted from the opening when a voltage differential is applied between the first and a second electrodes. Chemical feedstock to be treated is then exposed to the non-thermal plasma. This processing is suited for the following exemplary chemical reactions as (i) partial oxidation of hydrocarbon feedstock to produce fictionalized organic compounds; (ii) chemical stabilization of a polymer fiber (e.g., PAN fiber precursor in carbon fiber production; (iii) pre-reforming of higher chain length petroleum hydrocarbons to generate a feedstock suitable for reforming; (iv) natural gas reforming in a chemically reducingatmosphere (e.g., ammonia or urea) to produce carbon monoxide andhydrogen gas; or (v) plasma enhanced water gas shifting.