How is the pressure of a gas related to its concentration of particles? a) pressure will expand a gas, enlarging its volume and reducing its density and concentration of particles. b) pressure will magnify a gas, developing its volume and multiplying its density and concentration of particles. c) pressure will compress a gas, reducing its volume and giving it a greater density and concentration of particles. d) pressure will accelerate a gas, extending its volume and allowing a smaller density and concentration of particles.