Physical Chemistry Questions

An ideal gas is allowed to expand both reversibly and irreversibly in an isolated system. If $T_i$ is the initial temperature and $T_f$ is the final temperature, which of the following statements is correct?

($\Delta H-\Delta U$) for the formation of carbon monoxide ($\text{CO}$) from its elements at $298\text{K}$ is ($R=8.314{\text{J K}}^{-1}{\text{ mol}}^{-1}$):

$18\text{g}$ of glucose (${\text{C}}_6{\text{H}}_{12}{\text{O}}_6$) is added to $178.2\text{g}$ of water. The vapour pressure of water for this aqueous solution at $100^{\circ }\text{C}$ is:

The standard enthalpy of formation for $\text{ICl}(g)$ is calculated from:${\text{Cl}}_2(g)=2\text{Cl}(g),\Delta H=242.3$${\text{I}}_2(g)=2\text{I}(g),\Delta H=151.0$$\text{ICl}(g)=\text{I}(g)+\text{Cl}(g),\Delta H=211.3$${\text{I}}_2(s)={\text{I}}_2(g),\Delta H=62.76$ Standard states are ${\text{I}}_2(s)$ and ${\text{Cl}}_2(g)$.

Density of a $2.05\text{M}$ solution of acetic acid in water is $1.02\text{g/mL}$. The molality of the solution is:

The ionic mobility of alkali metal ions in aqueous solution is maximum for:

Resistance of a conductivity cell filled with a $0.1\text{M}$ solution of an electrolyte is $100\Omega$. The conductivity is $1.29{\text{S m}}^{-1}$. Resistance of the same cell when filled with $0.2\text{M}$ of the same solution is $520\Omega$. The molar conductivity of $0.2\text{M}$ solution of the electrolyte will be:

The following mechanism has been proposed for the reaction of $\text{NO}$ with ${\text{Br}}_2$ to form $\text{NOBr}$:$\text{NO}(g)+{\text{Br}}_2(g)\rightleftharpoons {\text{NOBr}}_2(g)\text{ (fast)}$${\text{NOBr}}_2(g)+\text{NO}(g)\to 2\text{NOBr}(g)\text{ (slow)}$ If the second step is the rate determining step, the order of the reaction with respect to $\text{NO}(g)$ is:

Given at $25^{\circ }\text{C}$:$\text{AgI}+e^{-}\to \text{Ag}+{\text{I}}^{-},E^{\circ }=-0.152\text{V}$${\text{Ag}}^{+}+e^{-}\to \text{Ag},E^{\circ }=0.800\text{V}$ What is the value of $\log K_{sp}$ for $\text{AgI}$? ($\frac{2.303RT}{F}=0.059\text{V}$)

The equilibrium constant for the reaction ${\text{SO}}_3(g)\rightleftharpoons {\text{SO}}_2(g)+\frac{1}{2}{\text{O}}_2(g)$ is $K_c=4.9\times 10^{-2}$. The value of $K_c$ for the reaction $2{\text{SO}}_2(g)+{\text{O}}_2(g)\rightleftharpoons 2{\text{SO}}_3(g)$ will be:

Rate of a reaction can be expressed by Arrhenius equation as $k=A{e}^{-E_a/RT}$. In this equation, $E_a$ represents:

In Langmuir’s model of adsorption of a gas on a solid surface:

Which one of the following sets of ions represents a collection of isoelectronic species?

The increasing order of the first ionization enthalpies of the elements B, P, S and F (lowest first) is:

The molar conductivities ${\Lambda }_{\text{NaOAc}}^{\circ }$ and ${\Lambda }_{\text{HCl}}^{\circ }$ at infinite dilution in water at $25^{\circ }\text{C}$ are $91.0$ and $426.2{\text{S cm}}^2/\text{mol}$ respectively. To calculate ${\Lambda }_{\text{HOAc}}^{\circ }$, the additional value required is:

Among the following mixtures, dipole-dipole as the major interaction, is present in:

The standard enthalpy of formation ($\Delta H_f^{\circ }$) at $298\text{K}$ for methane, ${\text{CH}}_4(g)$, is $-74.8{\text{kJ mol}}^{-1}$. The additional information required to determine the average energy for $\text{C}-\text{H}$ bond formation would be:

Phosphorus pentachloride dissociates as follows, in a closed reaction vessel, ${\text{PCl}}_5(g)\rightleftharpoons {\text{PCl}}_3(g)+{\text{Cl}}_2(g)$. If total pressure at equilibrium of the reaction mixture is $P$ and degree of dissociation of ${\text{PCl}}_5$ is $x$, the partial pressure of ${\text{PCl}}_3$ will be:

Uncertainty in the position of an electron ($\text{mass}=9.1\times 10^{-31}\text{kg}$) moving with a velocity $300\text{m/s}$, accurate up to $0.001\%$, will be ($h=6.63\times 10^{-34}\text{Js}$):

A reaction was found to be second order with respect to the concentration of carbon monoxide. If the concentration of carbon monoxide is doubled, with everything else kept the same, the rate of reaction will:

Total volume of atoms present in a face-centre cubic (FCC) unit cell of a metal is ($r$ is atomic radius):

Which of the following molecules/ions does not contain unpaired electrons?

According to Bohr’s theory, the angular momentum of an electron in $5\text{th}$ orbit is:

How many moles of magnesium phosphate, ${\text{Mg}}_3({\text{PO}}_4{)}_2$ will contain $0.25\text{mole}$ of oxygen atoms?