Which element has the same number of electrons in the outermost energy level at Lithium?

Hydrogen, lithium, sodium, and potassium all have 1 valence electron ( an electron in the outermost energy level is a valence electron).

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.

fe 55.85 g/mol and h2o 18.02 g/mol.