Question

write an activity to observe the speed of diffusion of two gases

Answer 1

Answer: when you apply a perfume to any body you can smell it quickly.

Explanation: activity1  

when the particles of perfume join the atmosphere, the particles of perfume and the air(atmosphere) diffuse(when the particles of two different types of matter intermix own its own)causing to spread the fragrance  .

activity 2  

you can get smell of hot sizzling fod in a second from far because its kinatic energy(heat energy) makes he particles to spread quickly but cold food we cannot smell beacouse its kinatic energy(heat energy) is mostly goen

by this acitivity we can say that particles are continusly moving.

And depending on the kinatic energy it happens fast if more and slow if its less

i hope you got your answer .