What are the main states of matter?

At $400 \ K$ temperature in a closed vessel,the $\%$ by volume of $He, Ne$,and $Ar$ are $40\%, 40\%$,and $20\%$ respectively. If the total pressure is $25 \ bar$,find the partial pressure of each gas.

Gas $X$ diffuses three times faster than gas $Y$. What is the ratio of their densities,i.e.,$D_x : D_y$?

At a certain temperature and pressure,helium diffuses $n$ times faster than methane. Find the value of $n$.

The rate of diffusion of $SO_{2}$,$CO_{2}$,$PCl_{3}$ and $SO_{3}$ are in the following order:

When a bottle of perfume is opened in a closed room of $1000\,m^3$,the fragrance spreads throughout the room. Which property of gases is responsible for this?