List of top Chemistry Questions on Gaseous State

At \(27^\circ C\), a real gas of molar mass \[ 44\ \text{g mol}^{-1} \] occupies a volume of \[ 0.4\ \text{L} \] at a pressure of \[ 40\ \text{atm}. \] If the compressibility factor is \[ Z=0.65, \] what is its weight (in g)? \[ (R=0.082\ \text{L-atm K}^{-1}\text{mol}^{-1}) \]

When \(160\,\mathrm{g}\) of methane was burnt in air at STP, \(5\%\) of it remained. At \(273\,\mathrm{K}\) and \(1\,\mathrm{bar}\) pressure, air contains \(20\%\) of \(\mathrm{O_2}\) by volume. What is the approximate volume (in L) of air consumed? \[ \text{(At STP molar volume }=22.71\,\mathrm{L}) \]

At \(300\,\mathrm{K}\), the diffusion rate of one mole of an ideal gas is \(0.082\,\mathrm{L\,s^{-1}}\). What is the pressure (in atm) of this gas which can diffuse in \(100\,\mathrm{s}\)? \[ \left(R=0.082\,\mathrm{L\,atm\,mol^{-1}\,K^{-1}}\right) \]

A gas mixture contains \(64\%\) methane and \(36\%\) ethane by mass. The density of the mixture at \(27^\circ\mathrm{C}\) and \(750\ \mathrm{mmHg}\) pressure (in \(\mathrm{g\,L^{-1}}\)) is \[ (\text{At. wt. of C}=12,\; \text{H}=1,\; R=0.082\ \mathrm{L\,atm\,K^{-1}\,mol^{-1}}) \]

At \(T(K)\), the rms velocity of an ideal gas is \(x\,\text{m s}^{-1}\). At what temperature (in K), the rms velocity becomes \(3x\,\text{m s}^{-1}\)?

At 300 K, one mole of a gas present in a 10 L flask exerted a pressure of 2.71 atm. What is its compressibility factor? \((R=0.082~L~atm~mol^{-1}K^{-1})\)

For a fixed amount of an ideal gas, its pressure is measured as a function of volume at three different temperatures ($T_1, T_2, T_3$). What is the correct order of temperatures? figure [H]

figure

The value of the gas constant $R$ in $\text{J K}^{-1}\text{ mol}^{-1}$ is

Which of the following pairs of gases contains the same number of molecules?

A balloon filled with an air sample occupies 3 L volume at 35 °C. On lowering the temperature to T, the volume decreases to 2.5 L. The temperature T is [Assume P constant]

Sum of molar mass of gas $(x) & (y)$ is :

100 mL of a hydrocarbon is mixed with 360 mL of oxygen and ignited. After combustion, the gaseous mixture has a volume of 280 mL at NTP. After passing through KOH, 80 mL of gas remains. The hydrocarbon is:

The compressibility factor (\(Z = \dfrac{PV}{nRT}\)) for an ideal gas is:

Mean velocity, most probable velocity and root mean square velocity of gas molecules are approximately in the ratio:

The fraction of molecules of a gas possessing velocities in a given range, as given by the Maxwell-Boltzmann distribution, depends on:

Identify a molecule having highest number of lone pair of electrons in valence shell of central atom.

What is vapour density of \(\text{O}_2\) gas?

Which among the following has lowest boiling point?

The unit of van der Waals constant ‘a’ is

The expression of average speed (u avg) of molecules of a gas is given by

What is the density of one mole of He (molar mass \(=4\ g\ mol^{-1}\)) at \(300\ K\) and a pressure of \(0.82\ atm\)? \((R=0.082\ L\ atm\ mol^{-1}\ K^{-1})\)

20 mL of gas \(A\) and 10 mL of gas \(B\) diffuse through a porous membrane separately in 1 minute. If the vapor density of \(B\) is \(X\), what is the vapor density of \(A\)?

The ratio of rate of diffusion of \(SO_2\) to \(CH_4\) is: