Thermodynamics PYQs Set 12 (PDF)

Set 12 of 14 · Questions 331-360 of 393

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Mere Teacher · Previous Year Questions NEET Chemistry · Thermodynamics · Set 12 (Q331-360)
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331. $Consider the following liquid‐vapour equilibrium. Liquid - Vapour Which of the following relations is correct?$ (1) $\frac{d ln P}{d T ^{2}} = \frac{- Δ H _{v}}{T ^{2}}$ (2) $\frac{d ln P}{dT} = \frac{Δ H _{v}}{R T ^{2}}$ (3) $\frac{d ln G}{d T ^{2}} = \frac{Δ H _{v}}{R T ^{2}}$ (4) $\frac{d ln P}{dT} = \frac{- Δ H _{v}}{RT}$ 332. $When disorder of a system increases, the change is said to be$ (1) $Exothermic$ (2) $Non-spontaneous$ (3) $Endothermic$ (4) $Spontaneous$ 333. $For a particular reaction DH° = - 76.6 KJ and DS° = 226 J K^{-1} . This reaction is:$ (1) $Spontaneous at all temperatures$ (2) $Non spontaneous at all temperatures$ (3) $Spontaneous at temperature below 66°C$ (4) $Spontaneous at temperature above 66°C$ 334. $For the reaction N_{2} + 3 H_{2} ⇋ 2 N H_{3}, Δ H = ?$ (1) $Δ E + 2 RT$ (2) $ΔE-2RT$ (3) $Δ H = RT$ (4) $Δ E - RT$ 335. $The entropy of crystalline substances at absolute zero going by the third law of thermodynamics should be taken as$ (1) $100$ (2) $50$ (3) $Zero$ (4) $Different for different substances$ 336. $A reaction having equal energies of activation for forward and reverse reactions has$ (1) $Δ H = 0$ (2) $Δ H = Δ G = Δ S = 0$ (3) $Δ S = 0$ (4) $Δ G = 0$ 337. $Identify false statement regarding isothermal process from following.$ (1) $System can exchange heat energy with the surrounding.$ (2) $Enthalpy of system remains constant.$ (3) $Temperature of systems remains constant.$ (4) $Internal energy of system remains constant.$ 338. $Mixing of non-reacting ideal gases is generally accompanied by$ (1) $Decrease in entropy$ (2) $Increase in entropy$ (3) $Change in enthalpy$ (4) $Increase in free energy$ 339. $At 27Clatent heat of fusion of a compound is 2930 J / mol . Entropy change is$ (1) $9.77 J/mol‐K$ (2) $10.77 J/mol‐K$ (3) $9.07 J/mol‐K$ (4) $0.977 J/mol‐K$ 340. $A sample of liquid in a thermally insulated container (a calorimeter) is stirred for 2 hr. by a mechanical linkage to a motor in the surrounding, for this process :$ (1) $w< 0; q = 0; Δ U = 0$ (2) $w > 0; q > 0; Δ > 0$ (3) $w< 0; q > 0; ∆ = 0$ (4) $w > 0; q = 0; Δ > 0$ 341. $Which amongst the following options is the correct relation between change in enthalpy and change in internal Energy?$ (1) $Δ H + Δ U = Δ nR$ (2) $Δ H = Δ U - Δ n_{g} RT$ (3) $Δ H = Δ U + Δ n_{g} RT$ (4) $Δ H - Δ U = - Δ nRT$ 342. $Identify the reaction/process in which the entropy increases.$ (1) $H (g) + H (g) \to H_{2} (g)$ (2) $H_{2} O (g) \to H_{2} O (s)$ (3) $H_{2} O (1) \to H_{2} O (g)$ (4) $A (g) + B (g) + C (s) \to 2 D (s)$ 343. $Five moles of an ideal gas at 1 bar and 298K is expanded into vacuum to double the volume. The work done is :$ (1) $Zero$ (2) $- RT ln V_{2} / V_{1}$ (3) $C_{v} (T_{2} - T_{1})$ (4) $- RT (V_{2} - V_{1})$ 344. $Mixing of non-reacting gases is generally accompanied by$ (1) $Decrease in entropy$ (2) $Increase in entropy$ (3) $Change in enthalpy$ (4) $Change in free energy$ 345. $The standard reaction Gibbs energuy for a chemical reaction at an absolute temperature T is given by DG° = A - BT, where A and B are non-zero constants. Which of the following is TRUE about this reaction ?$ (1) $Endothermic if A > 0$ (2) $Exothermic if B < 0$ (3) $Exothermic if A > 0 and B < 0$ (4) $Endothermic if A < 0 and B > 0$ 346. $The entropy of a perfectly crystalline solid at absolute zero is$ (1) $Positive$ (2) $Negative$ (3) $Zero$ (4) $Not definite$ 347. $200 joules of heat was supplied to a system at constant volume. It resulted in the increase in temperature of the system from 298 to 323 K. what is the change in internal energy of the sytem?$ (1) $400 J$ (2) $200 J$ (3) $50 J$ (4) $150 J$ 348. $When the value of entropy is greater, then the ability of work$ (1) $Is maximum$ (2) $Is minimum$ (3) $Is medium$ (4) $None of these$ 349. $Which one among the following is the correct option for right relationship between C_{p} and C_{v} for one mole of ideal gas?$ (1) $C_{P} - C_{V} = R$ (2) $C_{p} = RC_{V}$ (3) $C_{v} = R C_{p}$ (4) $C_{p} + C_{v} = R$ 350. $At absolute zero, the entropy of a pure crystal is zero. This is.$ (1) $First law of thermodynamics$ (2) $Second law of thermodynamics$ (3) $Third law of thermodynamics$ (4) $Zeroth law of thermodynamics$ 351. $Identify the reaction/process in which the entropy decreases$ (1) $H_{2} O (l) \to H_{2} O (s)$ (2) $H_{2} O (l) \to H_{2} O (g)$ (3) $H_{2} O (g) \to 2 H (g)$ (4) $Crystal (100 K) \to Crystal (200 K)$ 352. $An ideal gas undergoes isothermal compression from 5 m^{3} to 1 m^{3} against a constant external pressure of 4 N m^{-2} . Heat released in this process is used to increase the temperature of 1 mole of Al. If molar heat capacity of Al is 24 J m o l^{-1} K^{-1}, the temperature of Al increases by:$ (1) $\frac{3}{2} K$ (2) $\frac{2}{3} K$ (3) $1 K$ (4) $2 K$ 353. $Arrange the following in order of magnitude of work done by the system/on the system at constant temperature. (i) (w_{reversible}) for expansion in infinite stages. (ii) (w_{irreversible}) for expansion in single stage. (iii) (w_{reversible}) for compression in infinite stages. (iv) (w_{irreversible}) for compression in single stage. Choose the correct answer from the options given below:$ (1) $iv > iii = i > ii$ (2) $iii = i > iv > ii$ (3) $i > iii > ii > iv$ (4) $i > ii > iii > iv$ 354. $For the following reaction : C a C O_{3} (s) ¾® CaO (s) + C O_{2} (g) If at 0K, DS for the reaction is x cal/mol then entropy of C O_{2} (g) at 0K is:$ (1) $- x cal$ (2) $- 2x cal$ (3) $+ x cal$ (4) $0 cal$ 355. $The standard enthalpy of formation of CO_{2} (g), CaO (s) and CaCO_{3} (s) are - 393, - 634, - 1210 kJ mol^{- 1} respectively. If all the substances are in standard state, the standard enthalpy of decomposition of calcium carbonate to CaO (s) and CO_{2} (g) (in kJ mol^{- 1}) is$ (1) $969$ (2) $183$ (3) $-969$ (4) $-183$ 356. $In a spontaneous process, the entropy of the system and its surroundings$ (1) $Equals zero$ (2) $Decreases$ (3) $Increases$ (4) $Remains constant$ 357. $A container has hydrogen and oxygen mixture in ratio of 4 : 1 by weight, then$ (1) $Internal energy of the mixture decreases$ (2) $Internal energy of the mixture increases$ (3) $Entropy of the mixture increases$ (4) $Entropy of the mixture decreases$ 358. $During compression of a spring the work done is 10 kJ and 2 kJ escaped to the surroundings as heat. The change in internal energy, Δ U (in kJ) is:$ (1) $- 12$ (2) $- 8$ (3) $8$ (4) $-4$ 359. $The entropy values (in J K^{- 1} m o l^{- 1}) of H_{2 (g)} = 130.6, C l_{2 (g)} = 223.0 and H C l_{(g)} = 186.7 at 298 K and 1 atm pressure. Then entropy change for the reaction H_{2 (g)} + C l_{2 (g)} \to 2 H C l_{(g)} is$ (1) $+ 540.3$ (2) $+ 727.3$ (3) $- 166.9$ (4) $+ 19.8$ 360. $Standard entropy change for the above reaction is$ (1) $60.3 JK^{- 1} mol^{- 1}$ (2) $80.7 JK^{- 1} mol^{- 1}$ (3) $- 70 JK^{- 1} mol^{- 1}$ (4) $+ 10.7 JK^{- 1} mol^{- 1}$