2. Why are negative ions usually larger than positive ions?

Explanation:

When an atoms attracts extra electrons it becomes a negative ion. The negative ion is larger than the original atom. The positive nucleus remains the same, with the same attractive force. ... This means with more electrons but the same number of positive protons, the size of the ionic radius will increase.

hope you got the answer

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.