Thermodynamics PYQs Set 8 (PDF)

Set 8 of 14 · Questions 211-240 of 393

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Mere Teacher · Previous Year Questions NEET Chemistry · Thermodynamics · Set 8 (Q211-240)
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211. $The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy changes for the melting of ice at 0^{o} C is$ (1) $10.52 cal/ (mol K)$ (2) $21.04 cal/ (mol K)$ (3) $5.260 cal/ (mol K)$ (4) $0.526 cal/ (mol K)$ 212. $Conversion of oxygen into ozone is non spontaneous at$ (1) $all temperatures$ (2) $high temperature$ (3) $room temperature$ (4) $low temperature.$ 213. $Which of the following options are correct? A B C D Δ_{r} H^{\circ} + + - + Δ S^{\circ} + + - - Δ_{r} G^{\circ} + - - + Spontaneity of the reaction Spontaneous at low T Spontaneous at high Spontaneous at low T Spontaneous at high T$ (1) $A, B and C$ (2) $B only$ (3) $B and C$ (4) $C and D$ 214. $Among the following, the set of parameters that represents path functions, is: (i) q + w (ii) q (iii) w (iv) H - TS$ (1) $(ii) and (iii)$ (2) $(ii), (iii) and (iv)$ (3) $(i) and (iv)$ (4) $(i), (ii) and (iii)$ 215. $For a reaction, A(g) ® A (l); DH = -3RT. The correct statement for the reaction is:$ (1) $DH = DU ¹ O$ (2) $\|DH\| > \|DU\|$ (3) $\|DH\| < \|DU\|$ (4) $DH = \|DU = O$ 216. $The bond enthalpies of heavy hydrogen, O - O and D - O are + 400, + 498 and + 490 kJ mol^{- 1}, respectively. The Δ H^{\circ} of the reaction to produce D_{2} O is$ (1) $- 300 kJ mol^{- 1}$ (2) $- 331 kJ mol^{- 1}$ (3) $29.1 kJ mol^{- 1}$ (4) $2.91 kJ mol^{- 1}$ 217. $The variation of equilibrium constant with temperature is given below: Temperature Equilibrium Constant T_{1} = 25°C K_{1} = 10 T_{2} = 100°C K_{2} = 100 The values of ∆ H°, ∆ G° at T_{1} and ∆ G° at T_{2} (in kJ mo 1^{- 1}) respectively, are close to [Use R = 8.314J K^{- 1} mo 1^{- 1}]$ (1) $28.4,-5.71 and -14.29$ (2) $0.64,-7.14 and -5.71$ (3) $28.4,-7.14 and -5.71$ (4) $0.64,-5.71 and -14.29$ 218. $Ice at - 5^{\circ} C is heated to become vapor with temperature of 110^{\circ} C at atmospheric pressure. The entropy change associated with this process can be obtained from$ (1) $\int_{268 K}^{273 K} C_{p}, mdT + \frac{Δ H _{m} , fusion}{T _{f}} + \frac{Δ H _{m} , vaporisation}{T _{b}} + \int_{273 K}^{373 K} C_{p}, mdT + \int_{373 K}^{383 K} C_{p}, mdT$ (2) $\int_{268 K}^{273 K} \frac{C p , m}{T} dT + \frac{Δ H _{m} , fusion}{T _{f}} + \frac{Δ H _{m} , vaporisation}{T _{b}} + \int_{273 K}^{373 K} \frac{C _{p, m} dT}{T} + \int_{373 K}^{383 K} \frac{C _{p, m} dT}{T}$ (3) $\int_{268 K}^{383 K} C_{p} dT + \frac{q rev}{T}$ (4) $\int_{268 K}^{383 K} C_{p} dT + \frac{Δ H _{melting}}{273} + \frac{Δ H _{boiling}}{373}$ 219. $A liquid when kept inside a thermally insulated closed vessel at 25^{\circ} C was mechanically stirred from outside. What will be the correct option for the following thermodynamic parameters?$ (1) $Δ U < 0, q = 0, w > 0$ (2) $Δ U = 0, q = 0, w = 0$ (3) $Δ U > 0, q = 0, w > 0$ (4) $Δ U = 0, q < 0, w > 0$ 220. $Consider the following data: Δ_{f} H^{⊖} (methane, g) = - XkJmol^{- 1} Enthalpy of sublimation of graphite = YkJmol^{- 1} Dissociation enthalpy of H_{2} = ZkJmol^{- 1} The bond enthalpy of C - H bond is given by :$ (1) $- X + Y + Z 4$ (2) $\frac{X + Y + 4 Z}{2}$ (3) $\frac{X + Y + 2 Z}{4}$ (4) $X + Y + Z$ 221. $Match List I (Equations) with List II (Type of processes) and select the correct option. List I Equations A. K_{p} > Q B. Δ G^{o} < RT ln Q C. K_{p} = Q D. T > \frac{Δ H}{Δ S} List II Type of processes (i) Non-spontaneous (ii) Equilibrium (iii) Spontaneousand endothermic (iv) Spontaneous$ (1) $A - (i), B‐(ii), C‐(iii), D‐(iv)$ (2) $A‐(iii), B‐(iv), C‐(ii), D - (i)$ (3) $A‐(iv), B - (i), C‐(ii), D‐(iii)$ (4) $A‐(ii), B - (i), C‐(iv), D‐(iii)$ 222. $For the reaction, X_{2} O_{4 (l)} \to 2 X O_{2 (g)} Δ U = 2.1 kcal, Δ S = 20 cal K^{- 1} at 300 K Hence, Δ G is$ (1) $2.7 kcal$ (2) $- 2.7 kcal$ (3) $9.3 kcal$ (4) $- 9.3 kcal$ 223. $Which of the following statement is true. The entropy of the universe$ (1) $Increases and tends towards maximum value$ (2) $Decreases and tends to be zero$ (3) $Remains constant$ (4) $Decreases and increases with a periodic rate$ 224. $Consider the following processes: Δ H (kJ / mol) 1/2 A \to B + 150 3 B \to 2 C + D - 125 E + A \to 2 D + 350 For B + D \to E + 2 C, Δ H will be$ (1) $525 kJ/mol$ (2) $- 175 kJ/mol$ (3) $- 325 kJ/mol$ (4) $325 kJ/mol$ 225. $Which of the following is correct option for free expansion of an ideal gas under adiabatic condition?$ (1) $q = 0, Δ T \neq = 0, w = 0$ (2) $q \neq = 0, Δ T = 0, w = 0$ (3) $q = 0, Δ T = 0, w = 0$ (4) $q = 0, Δ T < 0, w \neq = 0$ 226. $At 500 K for an isobaric process. D S_{sy s t e m} = - 10 \frac{k J}{m o l K} and D S_{s u r r} = 12 \frac{k J}{m o l K} Therefore, DG for the entire process is-$ (1) $-500 kJ/mol$ (2) $-1000 kJ/mol$ (3) $-600 kJ/mol$ (4) $-1100 kJ/mol$ 227. $Enthalpy of hydrogenation of one mole of benzene to cyclohexane is [Resonance energy of benzene = - 150.4 kJ / mol, enthalpy of hydrogenation of cyclohexene = - 119.5 kJ / mol]$ (1) $- 208.1 kJ / mol$ (2) $- 358.1 kJ / mol$ (3) $+ 150.4 kJ / mol$ (4) $- 269.9 kJ / mol$ 228. $Assuming enthalpy of combustion of hydrogen at 273 K, - 286 kJ and enthalpy of fusion of ice at the same temperature to be + 6.0 kJ, calculate enthalpy change during formation of 100 g of ice.$ (1) $+ 1622 kJ$ (2) $- 1622 kJ$ (3) $+ 292 kJ$ (4) $- 292 kJ$ 229. $Consider the given data: (i) HCl (g) + 10 H_{2} O (l) \to HCl \cdot 10 H_{2} O Δ H = - 69.01 kJ mol^{- 1} (ii) HCl (g) + 40 H_{2} O (l) \to HCl . 40 H_{2} O Δ H = - 72.79 kJ mol^{- 1} Choose the correct statement: The heat of dilution for the$ (1) $HCl (HCl_{1} 10 H_{2} O) to (HCl . 40 H_{2} O) is 3.78 kJ mol^{- 1} .$ (2) $Dissolution of gas in water is an endothermic process.$ (3) $The heat of solution depends on the amount of solvent.$ (4) $The heat of formation of HCl solution is represented by both (i) and (ii)$ 230. $Enthalpy of C H_{4} + \frac{1}{2} O_{2} \to C H_{3} OH is negative. If enthalpy of combustion of C H_{4} and C H_{3} OH are x and y respectively. Then which relation is correct?$ (1) $x > y$ (2) $x < y$ (3) $x = y$ (4) $x^{3} y$ 231. $The standard enthalpy of atomization of ethane according to the equation C_{2} H_{6} (g) \to 2 C (g) + 6 H (g) is 622 kJ mol^{- 1} . If standard mean C - H bond dissociation enthalpy is 90 kJ mol^{- 1}, the standard mean dissociation enthalpy of C-C bond (in kJ mol^{- 1}) is$ (1) $540$ (2) $90$ (3) $85$ (4) $82$ 232. $The work done during combustion of 9 \times 10^{- 2} kg of ethane, C_{2} H_{6 (g)} at 300 K is (Given, R = 8.314 J deg^{- 1} mol^{- 1}, atomic mass C = 12, H = I)$ (1) $6.236 kJ$ (2) $- 6.236 kJ$ (3) $18.71 kJ$ (4) $- 18.71 kJ$ 233. $The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from a volume of 10 d m^{3} to a volume of 100 d m^{3} at 2 7^{0} C is:$ (1) $38.3 J m o l^{-1} K^{-1}$ (2) $35.8 J m o l^{-1} K^{-1}$ (3) $32.3 J m o l^{-1} K^{-1}$ (4) $42.3 J m o l^{-1} K^{-1}$ 234. $The enthalpy of vapourisation of a liquid is 30 kJ m o l^{-1} and entropy of vapourisation is 75 m o l^{-1} K. The boiling point of the liquid at 1 atm is$ (1) $250 K$ (2) $400 K$ (3) $450 K$ (4) $600 K$ 235. $The correct statement amongst the following is:$ (1) $The standard state of a pure gas is the pure gas at a pressure of 1 bar and temperature 273 K.$ (2) $Δ_{f} H_{500}^{\circ} is zero for O_{2} (g) .$ (3) $Δ_{f} H_{298}^{\circ} is zero for O (g) .$ (4) $The term 'standard state' implies that the temperature is 0^{\circ} C .$ 236. $The absolute enthalpy of neutralisation of the reaction: Mg O_{(s)} + 2 HC l_{(aq)} \to MgC l_{2 (aq)} + H_{2} O_{(l)} will be$ (1) $- 57.33 kJmo l^{- 1}$ (2) $greater than - 57.33 kJmo l^{- 1}$ (3) $less than - 57.33 kJmo l^{- 1}$ (4) $57.33 kJmo l^{- 1}$ 237. $Which of the following mixing of 1 M base and 1 M acid leads to the largest increase in temperature?$ (1) $30 mLCH_{3} COOH and 30 mL NaOH$ (2) $45 mLCH_{3} COOH and 25 mLNaOH$ (3) $30 mL HCl and 30 mL NaOH$ (4) $50 mL HCl and 20 mL NaOH$ 238. $For one mole of an ideal gas, which of these statements must be true? (A) U and H each depends only on temperature (B) Compressibility factor z is not equal to 1 (C) C_{P, m} - C_{v, m} = R (D) dU = C_{v} dT for any process$ (1) $(A) and (C)$ (2) $(A), (C) and (D)$ (3) $(B), (C) and (D)$ (4) $(C) and (D)$ 239. $In a closed insulated container a liquid is stirred with a paddle to increase the temperature which of the following is true?$ (1) $Δ E = W \neq = 0, q = 0$ (2) $Δ E = W = q \neq = 0$ (3) $Δ E = 0, W = q \neq = 0$ (4) $W = 0, Δ E = q \neq = 0.$ 240. $Standard entropy of X_{2}, Y_{2} and XY_{3} are 60, 40 and 50 J K^{-1} m o l^{-1}, respectively. For the reaction, \frac{1}{2} X_{2} + \frac{3}{2} Y_{2} \to XY_{3} ∆ H = - 30 kJ. To be at equilibrium the temperature will be:$ (1) $500 K$ (2) $750 K$ (3) $1000 K$ (4) $1250 K$