In this study the impact of bubble surface characterization (mobility or immobility), its diameter and velocity is investigated on inertial forces in particle-bubble collision efficiency (E-C). Three models including Sutherland (EC-SU), Schulze (EC-SC), and generalized Sutherland Equation (EC-GSE) were taken into account with regard to their differences from the inertial point of view in the particle size range of 1-100 mu m. Bubble diameters of 0.08, 0.12, and 0.15cm and bubble velocities of 10, 20 and 30cm/s were selected to study the flotation of chalcopyrite. Weber and Paddock collision model (EC-W&P) was taken for evaluation of the effect of bubble surface mobility on E-C. It was found that when the bubble diameter is 0.12cm, reducing bubble velocity from 30 to 20cm/s, the inertia force can be ignored for wider range of particle size. Corresponding particle size in cross-sectional point between GSE and Schulze collision models was introduced for better evaluation of the positive and negative particle inertial effects. The best agreement between them was taken for bubble diameter of 0.12cm and velocity of 20cm/s. It was concluded that the influence of bubble velocity is more effective than bubble diameter regarding its role on particle inertial forces in particle-bubble interaction.