It's all random movements, But if you have a place that you have more molocules than another place the molocules are going to have more collisons on the filled side than the empy so it is going to escape to the empty side.
motion of molocules-----> Kinetic energy.
No it is random motion
More temprture more motion in the molocules --> more mtion in the molcules more colisions(faster diffusion)
Passive= ATP needed & up gradiant
Active= no ATP needed & down gradint