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?

Define surface tension and provide its dimensions and $SI$ unit.

Two gases $A$ and $B$ having the same volume diffuse through a porous partition in $20$ and $10$ seconds respectively. The molecular mass of $A$ is $49 \ u$. The molecular mass of $B$ will be .............. $u$.

What is the ratio of the rates of diffusion of gases $A$ and $B$ having molecular weights $36$ and $64$ respectively?

During the evaporation of a liquid,the temperature of the liquid ..

$x \ g$ of molecular oxygen $(O_2)$ is mixed with $200 \ g$ of neon $(Ne)$. The total pressure of the nonreactive mixture of $O_2$ and $Ne$ in the cylinder is $25 \ bar$. The partial pressure of $Ne$ is $20 \ bar$ at the same temperature and volume. The value of $x$ is $....$ [Given: Molar mass of $O_2 = 32 \ g \ mol^{-1}$. Molar mass of $Ne = 20 \ g \ mol^{-1}$]