KCET (DEMO) CHEMISTRY THERMODYNAMICS PAPER

The process with negative entropy change is

An ideal gas undergoes isothermal compression from $$5 \mathrm{~m}^{3}$$ to $$1 \mathrm{~m}^{3}$$ against a constant external pressure of $$4 \mathrm{Nm}^{-2}$$. Heat released in this process is used to increase the temperature of 1 mole of Al . If molar heat capacity of Al is $$24 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$$, the temperature of Al increases by

Consider the reversible isothermal expansion of an ideal gas in a closed system at two different temperatures $$T_{1}$$ and $$T_{2}\left(T_{1}<T_{2}\right)$$. The correct graphical depiction of the dependence of work done (w) on the final volume $$(\mathrm{V})$$ is

A process has $$\Delta H=200 \mathrm{Jmol}^{-1}$$ and $$\Delta S=40 \mathrm{JK}^{-1} \mathrm{~mol}^{-}$$. Out of the values given below, choose the minimum temperature above which the process will be spontaneous

For the equilibrium, $$2 \mathrm{H}_{2} \mathrm{O} \leftrightarrow \mathrm{H}_{3} \mathrm{O}^{+}+\mathrm{OH}^{-}$$, the value of $$\Delta G^{0}$$ at 298 K is approximately

The reaction, $$M g O(s)+C(s) \longrightarrow M g(s)+C O(g)$$, for which $$\Delta_{r} H^{0}=+491.1 \mathrm{~kJ} \mathrm{~mol}^{-1}$$ and $$\Delta_{r} S^{0}=$$ $$198.0 \mathrm{KK}^{-1} \mathrm{~mol}^{-1}$$, is not feasible at 298 K . Temperature above which reaction will be feasible is

The standard reaction Gibbs energy for a chemical reaction at an absolute temperature T is given by $$\Delta_{r} G^{0}=A-B T$$ Where A and B are non-zero constants. Which of the following is TRUE about this reaction?

The entropy change associated with the conversion of 1 kg of ice at 273 K to water vapours at 383 K is (Specific heat of water liquied and water vapour are $$4.2 \mathrm{~kJ}^{-1} \mathrm{~kg}^{-}$$and $$2.0 \mathrm{~kJ}^{-1} \mathrm{~kg}^{-}$$; heat of liquid fusion and vapourisation of water are $$334 \mathrm{~kJ}^{-1}$$ and $$2491 \mathrm{~kJ} \mathrm{~kg}^{-}$$, respectively). ( $$\log 273=2.436, \log$$ $$373=2.572, \log 383=2.583)$$

Two blocks of the same metal having same mass and at temperature $$T_{1} a n d T_{2}$$, respectively, are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, $$\Delta \mathrm{S}$$, for this process is

For the chemical reaction $$X \leftrightarrow Y$$, the standard reaction Gibbs energy depends on temperature T (in K ) as
$$\Delta_{r} G^{0}\left(\right.$$ in kJ mol $$\left.^{-1}\right)=120-\frac{3}{8} T$$. The major component of the reaction mixture at T is

For a diatomic ideal gas in a closed system, which of the following plots does not correctly describe the relation between various thermodynamic quantities?

Given,
i) $$\mathrm{C}($$ graphite $$)+\mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}_{2}(\mathrm{~g}) ; \Delta_{r} \mathrm{H}^{\Theta}=x \mathrm{kJmol}^{-1}$$
ii) $$C($$ graphite $$)+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}(\mathrm{g}) ; \Delta_{r} \mathrm{H}^{\Theta}=\mathrm{ykJol}^{-1}$$
iii) $$\mathrm{CO}(g)+\frac{1}{2} \mathrm{O}_{2}(g) \rightarrow \mathrm{CO}_{2}(g) ; \Delta_{r} H^{\Theta}=\mathrm{zkJmol}^{-1}$$

Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?

Given i) $$2 \mathrm{Fe}_{2} \mathrm{O}_{2}(s) \rightarrow 4 \mathrm{Fe}(\mathrm{s})+3 \mathrm{O}_{2}(\mathrm{~g}) ; \Delta_{r} G^{0}=+1487.0 \mathrm{kJmol}^{-1}$$
ii) $$2 \mathrm{CO}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g}) \rightarrow 2 \mathrm{CO}_{2}(\mathrm{~g}) ; \Delta_{r} G^{0}=-514.4 \mathrm{kJmol}^{-1}$$
free energy change, $$\Delta_{r} G^{0}$$ for the reaction $$2 \mathrm{Fe}_{2} \mathrm{O}_{3}(s)+6 \mathrm{CO}(\mathrm{g}) \rightarrow 4 \mathrm{Fe}(s)+6 \mathrm{CO}_{2}(g)$$ will be

$$\Delta_{r} G^{0}$$ at 500 K for substance ‘ S ” in liquid state and gaseous state are $$+100.7 \mathrm{kcal}^{-1} \mathrm{~mol}^{-1}$$ and +103 kcal $$\mathrm{mol}^{-1}$$, respectively. Vapour pressure of liquid ‘ S ‘ at 500 K is approximately equal to

An ideal gas undergoes a cyclic process as shown in figure

$$
\begin{aligned}
& \Delta U_{B C}=-5 \mathrm{kJmol}^{-1}, q_{A B}=2 \mathrm{kJmol}^{-1} \\
& W_{A B}=-5 \mathrm{kmol}^{-1}, W_{C A}=3 \mathrm{kmol}^{-1}
\end{aligned}
$$

Heat absorbed by the system during process CA is