Where are electrons most likely to be found in the cloud?

nucleus

Explanation:

Electrons are found in clouds that surround the nucleus of an atom. Those clouds are specific distances away from the nucleus and are generally organized into shells. Because electrons move so quickly, it is impossible to see where they are at a specific moment in time.

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.