This work presented a double Gaussian equation for the activation energy distribution to illustrate the competition and coordination between the bridge scission and condensation. The selectivity coefficients for the two pathways were operated as a function of temperature. Zhundong coal will be taken as an example to show the rationality of this designation. The C-13 solid-state NMR, ultimate analyses, pyridine extraction test, and flash devolatilization test (Pyro-probe with a heating rate of 2000K.s(-1)) for Zhundong coal were conducted to validate the model. It was found from the NMR data that significant amount of carbonyl carbon was enriched initially in Zhundong coal. The prediction results show that bridge's scission will contribute to the escape of tar during the early and middle pyrolysis stages while its condensation will be responsible for the generation of non condensable gases throughout devolatilization. Moreover, the peripheral group is depleted when T > 1000 K.