An open vessel at $27\,^{\circ}C$ is heated until two-fifths of the air (assumed as an ideal gas) in it has escaped from the vessel. Assuming that the volume of the vessel remains constant,the temperature to which the vessel has been heated is:

What will be the pressure exerted by a mixture of $3.2 \ g$ of methane and $4.4 \ g$ of carbon dioxide contained in a $9 \ dm^3$ flask at $27^{\circ} C$?

The volume-temperature graph of a given mass of an ideal gas at constant pressure is shown below. What is the correct order of pressures?

Two separate bulbs contain ideal gases $A$ and $B$. The density of gas $A$ is $4$ times that of gas $B$. The molecular mass of $A$ is half that of gas $B$. The two gases are at the same temperature. The ratio of the pressure of $A$ to that of gas $B$ is

The density of gas $A$ is twice that of gas $B$ at the same temperature. The molecular weight of gas $B$ is twice that of gas $A$. The ratio of the pressure of gas $A$ to gas $B$ will be:

Air entering the lungs ends up in tiny sacs called alveoli. It is from the alveoli that oxygen diffuses into the blood. The average radius of the alveoli is $0.0050 \ cm$ and the air inside contains $14$ per cent oxygen. Assuming that the pressure in the alveoli is $1.0 \ atm$ and the temperature is $37 \ ^oC$,calculate the number of oxygen molecules in one of the alveoli.