Thermodynamics practice · Mixed difficulty

During isothermal expansion of an ideal gas, its

Equilibrium constant for a hypothetical
reaction, $A\left( g \right)f2B\left( g \right)$ at 400 K is $10^2M.$ At 500 K, for the same reaction,
equilibrium constant is $2 \times {10^2}M$. According
to Lechatelier’s principle, favourable
conditions for the formation of 'A' are

The $W / Q$ of a carnot engine is $1 / 6$. When temperature of sink is reduced by $62^{\circ} {C}$, this ratio becomes twice, therefore the initial temperature of the sink and source are:

Heat of formation of compound is defined as :

STATEMENT-1 : All combustion reactions are exothermic.

STATEMENT-2 : Enthalpies of products are greater than enthalpies of reactants $\left(\Sigma v_p \Delta_f H(P)>\Sigma v_R \Delta_f H(R)\right)$

What is ∆n for combustion of 1 mole of benzene, when both the reactants and products are gas at 298 K

If the enthalpy change for the reaction is $2 \mathrm{NH}_{3(\mathrm{~g})} \rightarrow \mathrm{N}_{2(\mathrm{~g})}+3 \mathrm{H}_{2(\mathrm{~g})}$ is $92 \mathrm{~kJ} \mathrm{~mol}^{-1}$ the enthalpy of formation of ammonia is

The change in internal energy equals

Which of the following gas will liberate maximum heat on combustion per gram?

Select the correct statements.

The correct relation for $K_f$ is/are:

If at 298 K the bond energies of $C - H,\,C - C,\,C = C$ and $H - H$ are respectively, 414, 347, 615 and 435 ${\text{kJ}}\,{\text{mo}}{{\text{l}}^{ - 1}},$ the value of enthalpy change for the reaction ${H_2}C = C{H_2}\left( g \right) + {H_2}\left( g \right) \to {H_3}C - C{H_3}\left( g \right)$
at 298 K will be:

The temperature of $15 \mathrm{~ml}$ of a strong acid increases by $2^{\circ} \mathrm{C}$ when $15 \mathrm{~ml}$ of a strong base is added to it. If $5 \mathrm{~ml}$ of each are mixed, temperature should increase by

Temperature of 5 moles of a gas is decreased
by 2K at constant pressure. Indicate the correct
statement

In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is $C{H_3}OH\left( l \right) + \frac{3}{2}{O_2}\left( g \right) \to C{O_2}\left( g \right) + 2{H_2}O\left( l \right)$ At 298 K, standard Gibb’s energies of formation for $C{H_3}OH\left( l \right),\,{H_2}O\left( l \right)\,\,and\,\,C{O_2}\left( g \right)$ are -166.2, -237.2 and $- 394.4\mathrm{ }kJ\mathrm{ }mo{l^{ - 1}}$ respectively. If standard enthalpy of combustion of methanol is $- 726kJ\mathrm{ }mo{l^{ - 1}}$ efficiency of the fuel cell will be:

The latent heat of fusion of ice at $0^{\circ} \mathrm{C}$ being $1.44 \mathrm{~k~cal} \mathrm{~mol}^{-1}$ and difference in heat capacity of ice and water being $9.3 \mathrm{~cal} \mathrm{~mol}^{-1}$, thus latent heat of fusion of ice at $-27^{\circ} \mathrm{C}$ is

Which of the following is an intensive property?

Statement I: The final temperature of an ideal
gas in adiabatic compression is less in reversible
compression than in irreversible compression
against a constant external pressure.

Statement II: The magnitude of work done on
an ideal gas in adiabatic compression is more in
irreversible process than that in reversible process.

A gas present in a cylinder fitted with a frictionless piston expands against a constant pressure of $1 {~atm}$ from a volume of 2 litre to a volume of 6 litre. In doing so, it absorbs $800 {~J}$ heat from surroundings. Determine increase in internal energy of process.

$\mathrm{H}_2 \mathrm{S}(\mathrm{g}) \rightarrow \mathrm{HS}^{-}(\mathrm{g})+\mathrm{H}^{+}(\mathrm{g}), \Delta \mathrm{H}^{\circ}=\mathrm{x}_1,$
$\Delta \mathrm{H_f^\circ}\left(\mathrm{H}_2 \mathrm{S}\right. (\mathrm{g})) =\mathrm{x}_2, \Delta \mathrm{H_f^\circ}\left(\mathrm{H}^{+}(\mathrm{g})\right)=\mathrm{x}_3$
Hence, $\Delta \mathrm{H_f^\circ}\left(\mathrm{HS}^{-}\right)$ is:

The heat of combustion of carbon monoxide at constant pressure and at constant volume at $27^{\circ} \mathrm{C}$ will differ from one another by:

The standard enthalpies of formation of $C{O_2}\left( g \right),\,\,{H_2}O\left( l \right)$ and glucose (s) at ${25^\mathrm{o}}\,\,C$ are $- 400\,\,KJ \cdot mo{l^{ - 1}},\,\, - 300\,\,KJ \cdot mo{l^{ - 1}}$ and $- 1300\,\,KJ/mol$ respectively. The standard enthalpy of combustion per gram of glucose at ${25^\mathrm{o}}\,\,C$ is

A: Dissolution of sugar in water proceed via increases in entropy.
R: Entropy decreases when egg is hard boiled.

${\mathrm{C}_{\mathrm{diamond}}} + {\mathrm{O}_2} \to \mathrm{C}{\mathrm{O}_2};\Delta H$=-395.3 kJ/mol
${\mathrm{C}_{\mathrm{graphite}}} + {\mathrm{O}_2} \to \mathrm{C}{\mathrm{O}_2};\Delta H$=-393.4 kJ/mol
${\mathrm{C}_{\mathrm{graphite}}} \to {\mathrm{C}_{\mathrm{diamond}}};\Delta \mathrm{H}$=?

Given that $\mathrm{C}+\mathrm{O}_2 \rightarrow \mathrm{CO}_2, \Delta \mathrm{H}^{\circ}=-\mathrm{x} \mathrm{~kJ}$

$2 \mathrm{CO}+\mathrm{O}_2 \rightarrow 2 \mathrm{CO}_2, \Delta \mathrm{H}^{\circ}=-\mathrm{y} \mathrm{~kJ}$

What is heat of formation of $\mathrm{CO}$?

For an adiabatic expansion of a perfect gas ∆P/P is equal to:

In the following reaction,

$\begin{aligned} & \mathrm{HF}(a q)+\mathrm{NaOH}(a q) \longrightarrow \mathrm{NaF}(a q)+\mathrm{H}_2 \mathrm{O}(l) ; \Delta H^\circ=-68.6 \mathrm{~kJ}^3 \mathrm{mol}^{-1} \\ \end{aligned}$

This value is much higher than the heat of neutralisation of strong acid with strong base $\left(-57.3 \mathrm{~kJ} \mathrm{~mol}^{-1}\right)$. This is because

A quantity of $1 \text{ g}$ of water on evaporation at
atmospheric pressure forms $1671 \, \text{cm}^3$
of steam.
Heat of vaporization is $540 \text{ cal/g}.$ The approximate
increase in internal energy is (1 L – atom = 24 cal)

Calculate the number of $\mathrm{kJ}$ of heat necessary to raise the temperature of $60 \mathrm{~g}$ of aluminium from $35^{\circ} \mathrm{C}$ to $55^{\circ} \mathrm{C}$. Molar heat capacity of ${Al}$ is $24 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$.

The enthalpy of formation of HI is 30.4 kJ. Which statement is false according to this observation?