$A$ $5.75 \ g$ sample of a gas occupies $3.5 \ L$ at $55 \ ^oC$ and $0.940 \ atm$ pressure. What is the molecular weight of the gas?

The ratio of densities of two gases is $1 : 2$. If the ratio of their temperatures is $2 : 1$,find the ratio of their corresponding pressures. (Assume the molar masses of the gases are equal.)

Pay load is defined as the difference between the mass of displaced air and the mass of the balloon. Calculate the pay load when a balloon of radius $10 \, m$,mass $100 \, kg$ is filled with helium at $1.66 \, bar$ at $27^{\circ} C$. (Density of air $= 1.2 \, kg \, m^{-3}$ and $R = 0.083 \, bar \, dm^{3} \, K^{-1} \, mol^{-1}$).

In the equation $PV = nRT$,which one cannot be the numerical value of $R$?

Which of the following graphs represents Boyle's law?

At what pressure will a quantity of gas occupy a volume of $60 \, mL$,if it occupies a volume of $100 \, mL$ at a pressure of $720 \, mm$ (assuming temperature is constant)?