Thermodynamics practice · Mixed difficulty

For the process to occur under adiabatic conditions, the correct condition is

What is the entropy change $(in J{K^{ - 1}}mo{l^{ - 1}})$ when one mole of ice is converted into water at 0℃? (The enthalpy change for the conversion of ice to liquid water is 6.0 kJ mol^(-1) at 0℃)

Assertion :- Enthalpy of graphite is lower than that of diamond.

Reason :- Entropy of graphite is greater than that of diamond.

Heat evolved in the reaction ${H_2} + C{l_2} \to 2\,HCl$ is 182 KJ. Bond energies of H-H and $Cl - Cl$ are 430 and 242 KJ/mol respectively. The $H - Cl$ bond energy is

For a spontaneous process, the correct statement is :

Using the data provided, calculate the multiple bond energy $(kJ\,mo{l^{ - 1}})$of a C≡C bond in ${\mathrm{C}_2}{\mathrm{H}_2}.$ Given that the heat of formation of ${\mathrm{C}_2}{\mathrm{H}_2}$ is $225kJmo{l^{ - 1}}$ (take the bond energy of C─H bond as $350\,\,kJ\,\,mo{l^{ - 1}}.):$
$2\mathrm{C}\left( s \right) \to 2\mathrm{C}\left( \mathrm{g} \right)\Delta H = 1410\,\,\mathrm{kJ\,\,mo}{\mathrm{l}^{ - 1}}$
$2\mathrm{C}\left( s \right) \to 2\mathrm{C}\left( \mathrm{g} \right)\Delta H = 1410\,\,\mathrm{kJ\,\,mo}{\mathrm{l}^{ - 1}}$
${\mathrm{H}_2}\left( \mathrm{g} \right) \to 2\mathrm{H}\left( \mathrm{g} \right)\Delta H = 330\,\,\mathrm{kJ\,\,mo}{\mathrm{l}^{ - 1}}$

ASSERTION (A) : For the combustion of methane, $\Delta U>\Delta H$

REASON (R): $\Delta H$ is related by $\Delta U$ by the expression $\Delta H=\Delta U+\Delta n R T$

$\mathrm{CCl}_2 \mathrm{F}_2$ cooled $1.25 \mathrm{~g}$ sample at constant atmospheric pressure of $1 \mathrm{~atm}$ from $320 \mathrm{~K}$ to $293 \mathrm{~K}$. During cooling the sample volume decreased from $274$ to $248 \mathrm{~mL}$. Calculate $\Delta {H}$ for the $\mathrm{CCl}_2 \mathrm{F}_2$ for this process. $\left(C_p=80.7 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right)$.

For the reactions,

(i) ${H}_2(\mathrm{~g})+{Cl}_2(\mathrm{~g}) \longrightarrow 2 {HCl}(\mathrm{g})+{xkJ}$

(ii) ${H}_2(\mathrm{~g})+{Cl}_2(\mathrm{~g}) \longrightarrow 2 {HCl}(\ell)+{ykJ}$

Which one of the following statement is correct :

When two moles of hydrogen expands isothermally against a constant pressure of 1 atm, at 25℃ from 15 L to 50 L, the work done (in litre atm) will be

The change in entropy, ∆S is positive for an endothermic reaction. If enthalpy charge ∆H occurs at the same temperature T, then the reaction is feasible:

For $A \rightarrow B, \Delta H=4 \mathrm{~kcal} \mathrm{~mol}^{-1}, \Delta S=10 \mathrm{~cal} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}.$ Reaction is spontaneous when temperature will be

The enthalpy of formation of water from hydrogen and oxygen is - 286 kJ $\mathrm{mo}{\mathrm{l}^{ - 1}}$. The enthalpy of decomposition of water into hydrogen and oxygen is:

The standard molar enthalpies of formation of $\mathrm{IF}_3(\mathrm{g})$ and $\mathrm{IF}_5(\mathrm{g})$ are $-470 \mathrm{~kJ}$ and $-847 \mathrm{~kJ},$ respectively. Valence shell electron-pair repulsion theory predicts that $\mathrm{IF}_5(\mathrm{g})$ is square pyramidal in shape in which all $\mathrm{I}-\mathrm{F}$ bonds are equivalent while $\mathrm{IF}_3(\mathrm{g})$ is T-shaped (based on trigonal-bipyramidal geometry) in which $\mathrm{I}-\mathrm{F}$ bonds are of different lengths. It is observed that the axial $\mathrm{I}-\mathrm{F}$ bonds in $\mathrm{IF}_3$ are equivalent to the $\mathrm{I}-\mathrm{F}$ bonds in $\mathrm{IF}_5.$ Calculate the equatorial $\mathrm{I}-\mathrm{F}$ bond strength in $\mathrm{IF}_3.$ Some other details given are as follows.

$\begin{aligned} & \mathrm{I}_2(\mathrm{s}) \rightarrow \mathrm{I}_2(\mathrm{g}): \Delta H=62 \mathrm{~kJ} \\ & \mathrm{F}_2(\mathrm{g}) \rightarrow 2 \mathrm{~F}(\mathrm{g}): \Delta H=155 \mathrm{~kJ} \\ & \mathrm{I}_2(\mathrm{g}) \rightarrow 2 \mathrm{I}(\mathrm{g}): \Delta H=149 \mathrm{~kJ} \end{aligned}$

The enthalpy of combustion of methane, graphite and dihydrogen at 298 K are –890.3 KJ/mol, –393.5 KJ/mol and –285.8 KJ/mol respectively. Enthalpy of formation of $C{H_4}\left( g \right)$ will be

Heat of formation of two moles of $\mathrm{NH}_3(\mathrm{~g})$ is $-90 \mathrm{KJ}$. Bond energies of $\mathrm{H}-\mathrm{H}$ and $\mathrm{N}-\mathrm{H}$ bonds are $435 \mathrm{KJ}$ and $390 \mathrm{KJ} \mathrm{mol}^{-1}$ respectively. The value of the bond energy of $N=N$ will be

Assertion : The increase in internal energy $(\Delta E)$ for the vaporization of one mole of water at $1 {~atm}$ and $373 {~K}$ is zero.

Reason : For all isothermal processes, $\Delta E=0$.

Statement I : In the following reaction, $C(s) + {O_2}(g) \to C{O_2}(g);\Delta H = \Delta E - RT$
Statement II : $\Delta H$ is related to $\Delta E$ by equation $\Delta H = \Delta E + \Delta {n_g}RT$

Statement-I : At equilibrium $\Delta {G^0}$ always zero.
Statement-II : At STP active masses of 11.2 L of ${O_2}\left( g \right)$ and 5.6 L of ${N_2}\left( g \right)$ are equal.

When water is added to quick lime, the reaction is :

Assertion (A): Volume of water in a pond is not a state function.
Reason (R): Volume of water is independent of the route by which water is filled in the pond either by rain or by tubewell or by both.

Determine whether or not, it is possible for sodium to reduce aluminium oxide to aluminium at $298 {~K}$. Also calculate equilibrium constant. Given that $G_f^{\circ}$ of ${Al}_2 {O}_3$ at $298 {~K}=-1582 {~kJ} {~mol}^{-1} ; G_f^0$ of ${Na}_2 {O}(s)$ at $298 {~K}$ $=-377 {~kJ} {~mol}^{-1}$.

The heat of neutralisation of a strong acid and a strong alkali is 57.0 kJ $\mathrm{mo}{\mathrm{l}^{ - 1}}$. The heat released when 0.5 mole of $\mathrm{HN}{\mathrm{O}_3}$ solution is mixed with 0.2 mole of KOH is

Heat of neutralisation of strong acid and strong base under $1 {~atm}$ and $25^{\circ} {C}$ is $-13.7\, {kcal}$. If standard Gibbs energy change for dissociation of water to ${H}^{+}$and ${OH}^{-}$ is $-19.14\, {kcal}$, the change in standard entropy for dissociation of water in $cal \,K \,{mol}^{-1}$ is :

Five moles of an ideal gas expand isothermally and reversibly from an initial pressure of $100 \mathrm{~atm}$ to a final pressure of $1 \mathrm{~atm}$ at $27^{\circ} \mathrm{C}.$ The work done by the gas is $(\ln 100=4.6)$

Given below are two statements one is labelled as Assertion (A) and the other is labelled as Reason (R)

Assertion (A): Heat of neutralisation of $HF$ (aq.) with ${NaOH}$ (aq.) is greater than $13.7 \mathrm{~Kcal}$.

Reason (R): Generally some heat is consumed in the ionisation of weak acid.
On the basis of above statements choose the most appropriate option from the following options:

A boiled egg show a/an …in entropy.

For an ideal monoatomic gas, molar heat capacity at constant volume $\left( {{C_v}} \right)$ is

The van’t Hoff reaction isotherm is:

${\mathrm{H}_2}\left( \mathrm{g} \right) + \frac{1}{2}{\mathrm{O}_2}\left( \mathrm{g} \right) \to {\mathrm{H}_2}\mathrm{O}\left( l \right);\Delta H = - 68\mathrm{kcal}$.The heat change, for the decomposition of 3.6 g of water is :