Answer:
force exerted per unit area by gas particles as they strike the surfaces around them
Step-by-step explanation:
According to the kinetic molecular theory, a gas is composed of molecules. The molecules of a gas are in constant random motion and collide frequently with each other as well as with the walls of the container.
Pressure is defined as force per unit area. The pressure of a gas is the force exerted per unit area by gas particles as they strike the surfaces around them hence the answer above.