What happens to the pressure of a gas if its volume is reduced?

Gas particles exert pressure by colliding with the walls of their container. If you reduce the volume, you are effectively increasing the density of the particles and they will collide with the walls more frequently, leading to an increase in pressure.

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.

it would be a gas formation