In a typical TAP experiment, a small amount of reactant gas is pulsed into a micro- or meso-reactor containing a catalyst. The reactor is usually evacuated to a high vacuum before the pulse, ensuring that the reactant interacts solely with the catalyst. After the pulse, the effluent gas is analyzed using a mass spectrometer or another detector to identify and quantify the products and intermediates as a function of time. This time-resolved data provides insights into the reaction kinetics and mechanisms.