Different diagnostic techniques are used to monitor the dynamics of electrons and Ar*(1s5) metastable atoms in the active plasma phase and in the afterglow of a capacitively coupled radio-frequency (RF) discharge operated in different gas mixtures and at different input powers. Diode laser absorption at 772.38 nm is used to measure the time resolved density of Ar*(1s5) atoms in either continuous-wave mode or pulsed RF discharges with 100 Hz pulsing frequency. Simultaneously, microwave interferometry recorded the time dependence of the electron density. Different plasma conditions, namely: (1) pure argon, (2) argon +5.9% acetylene before nanoparticle formation, (3) argon +5.9% acetylene after dust particles have been formed and (4) argon with dust particles remaining in the plasma volume but without acetylene are studied. The measured steady-state Ar*(1s5) density in the middle of the reactor is several times larger in the dusty argon plasma than in the pure argon discharge for the same discharge powers. At the same time, the electron density is several times less in the dusty plasma. These changes are caused by dust formation: the electric field in the bulk plasma is enhanced and thus consequently the electron temperature increases. Laser induced fluorescence (LIF) is used to measure the time and space resolved Ar*(1s5) axial distribution. In the pure argon discharge, the axial Ar*(1s5) metastable distribution has a characteristic saddle-like shape with maxima in the region of the sheaths. With dust particles inside, the axial distribution changes dramatically with the maximum at the discharge mid-plane, revealing an α–γ′ transition. The spatial distribution and absolute density of metastable atoms are influenced by the formation of a void in the cloud of nanoparticles. Depending on the size of the void, the Ar*(1s5) density reduction inside the void is between 30% and 50%. The high Ar*(1s5) metastable density in the dusty plasma afterglow strongly influences the time variation of the electron density in the afterglow. The observed increase of the electron density in the afterglow of the Ar/acetylene/dust plasmas is explained by the Penning ionization of acetylene by Ar*(1s5) metastable atoms. The time evolution of the electron density in the Ar/dust plasmas reveals that the nowadays assumed rate coefficient for generation of electrons by pooling reaction of Ar* metastable atoms is highly overestimated.