NEET Chemistry MCQs

A metal M forms a volatile carbonyl complex $M(CO)_x$. 0.525g of this complex is heated in a closed vessel of volume 250 mL at $50^\circ C$. The pressure inside the vessel after complete decomposition of the complex is 746 Torr. If the gas constant R is 0.0821 L atm $K^{-1} mol^{-1}$, what is the value of x in the formula $M(CO)_x$? (Assume the metal M does not contribute significantly to the pressure)

A mixture of $KClO_3$ and $KCl$ weighing 4.96 g was heated to produce $O_2$. The evolved oxygen occupied 448 mL at STP. What percent of the original mixture was $KClO_3$?

A mixture of 1 mol of He and 1 mol of CO$_2$ is contained in a vessel of volume V at 20°C. If the mixture behaves ideally, what is the pressure exerted by He?

Two separate containers of equal volume V contain ideal gases A and B at the same temperature T. The molar mass of A is twice that of B. The ratio of the densities of A and B ($\rho_A / \rho_B$) is:

A real gas most closely approaches ideal behavior under which of the following conditions?

A vessel contains an ideal gas at pressure P and temperature T. If the root mean square speed of the gas molecules doubles, keeping the volume constant, the new pressure P' will be:

At what temperature will the average translational kinetic energy of a gas molecule be equal to the energy required to break a bond of energy 2 eV? (Boltzmann constant $k_B = 1.38 imes 10^{-23} J/K$, $1 eV = 1.6 imes 10^{-19} J$)

An ideal gas undergoes a process in which its pressure P and volume V are related by $PV^n = constant$, where n is a constant. If the gas expands adiabatically ($n = \gamma$, where $\gamma = C_P/C_V$), which of the following statements is TRUE regarding the work done by the gas?

Two vessels are connected by a valve. One contains 10 g of $H_2$ at 27°C and 1 atm. The other contains 16 g of $O_2$ at 27°C and 1 atm. If the valve is opened and the gases mix completely, what is the partial pressure of $H_2$ in the mixture (assuming ideal behavior)?

A mixture of 1 mol of He and 0.5 mol of SO2 is held in a container at a constant temperature of 27°C. The partial pressure of He is 2 atm. If the mixture behaves ideally, what is the density of the mixture (g/L) closest to? (Given: R = 0.082 L atm/mol K, Molar mass of He = 4 g/mol, Molar mass of SO2 = 64 g/mol)