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Abstract A one-dimensional (1D) particle-in-cell/Monte Carlo collision (PIC/MCC) simulation study of nitrogen (N₂) capacitively coupled plasma (CCP) is presented for a pressure range between 0.1 and 1.5 Torr (13.33 – 199.98 Pa). The primary objective is to use moment analysis of charged particle data to systematically examine the validity of commonly employed assumptions in fluid plasma models for intermediate pressure CCPs. The voltage and pressure range investigated include the CCP operating in the α and γ modes as well as conditions with significant electron power absorption in the bulk plasma. At RF voltage V RF = 200 V (amplitude) and ion-induced secondary electron emission coefficient γ = 0.2, the bulk plasma region broadens with increasing pressure as a result of reduced electron and ion mean free paths. Electron power absorption increases in the bulk plasma at 0.5 Torr (66.66 Pa) and higher pressures, but it does not contribute significantly to plasma production. The plasma transitions from the α to γ mode as V RF is increased from 200 to 350 V at 0.1 Torr (13.33 Pa) with significant lowering of T e and increase of electron density (n e ) in the bulk plasma. The collision frequencies for individual electron impact reactions as well as the total collision frequency do not exhibit a straight-forward one-on-one relationship to electron temperature (T e ) or total electron energy (ε e ). This finding contrasts with the common assumption in fluid models for CCPs. Moment analysis of the momentum conservation equations reveals that the drift-diffusion approximation is valid for electrons in the bulk plasma and the pre-sheath region under both α- and γ-mode conditions. While ion momentum transport is dominated by sheath acceleration and collisional damping, the inertia term in the ion momentum equation is important at all pressures considered.