What is the nature of the $P$ versus $1/V$ graph at a constant temperature?

Find the value of the universal gas constant $R$ in $J \ mol^{-1} K^{-1}$.

Two vessels separately contain two ideal gases $A$ and $B$ at the same temperature. The pressure of gas $A$ is three times the pressure of gas $B$. Under these conditions,the density of gas $A$ is found to be two times the density of $B$. The ratio of molecular weights of gas $A$ and $B$ i.e. $\frac{M_A}{M_B}$ is

In the equation $PV = KT$,the value of $K$ depends on which factors?

An insulated cylindrical vessel is fitted with an insulated piston of negligible weight and negligible thickness at the midpoint of the vessel. The cylinder contains a gas at $0^{\circ} C$. When the gas is heated to $100^{\circ} C$, the piston moves through a length of $5 \, cm$. The length of the cylindrical vessel in $cm$ is:

Find the ratio of the density of air at the top of a mountain to the density of air at the bottom of the mountain,given the conditions shown in the image.