Tiêu đề Work Sheet - 1 (Chemical Equilibrium).pdf ✅

[SINGLE CORRECT CHOICE TYPE] Q.1. At total equilibrium pressure P1 atm and P2 atm, N2O4 is dissociated to an extent of 33.33% and 50% respectively. Ratio of 2 1 P P will be (A) 8 3 (B) 3 4 (C) 3 8 (D) 4 3 Q.2 For the reaction : PCl5 (g) PCl3 (g) + Cl2 ; K = 10 M at 600 K 0.1 mol of PCl5 (g) is placed in an evacuated 5L bulb. Then what would be the total pressure at equilibrium. (Take : R = 0.08 L-atm-mol–1 K–1] (A) 9.6 atm (B) 0.96 atm (C) 4.8 atm (D) 1.92 atm Q.3 The dissociation equilibrium of a gasAB2 can be represented as - 2AB2 (g) 2AB(g) + B2 (g) The degree of dissociation is 'x' and is small compared to 1. The expression relating the degree of dissociation (x) with equilibrium constant KP and total pressure P is - (A) (2KP /P)1/2 (B) KP /P (C) 2KP /P (D) (2KP /P)1/3 Q.4 At a given temperature the following reaction is allowed to reach equilibrium in a vessel of volume V1 litre. The degree of dissociation is1 .If at same temperature the volume of the reactionvessel is doubled (assuming the degrees of dissociation to be small ) the new degree of dissociation shall be – PCl5 PCl3 + Cl2 (A) 21 (B) 2 1 (C) 1 2 (D) 1 2  Q.5 For the reversible system, X(g) Y(g) + Z(g) a certain quantityof X was heated at pressure P at a certain temperature. The equilibrium partial pressure of X was found to be 7 P . What is the value of KP at given temperature (A) 7 P6 (B) 7 P9 (C) 7 P36 (D) 6P Q.6 The vapour density of N2O4 at a certain temperature is 30. What is the % dissociation of N2O4 at this temperature? (A) 53.3% (B) 106.6% (C) 26.7% (D) None Q.7 For the reaction : A .3H2O(s) A. H2O (s) + 2H2O(g) ; KP = 9 atm2 A24.63 litre flask contains 1 mole ofA. H2O(s) at 300 K. How manymoles of H2O(g) should be added to the flask at the given temperature to drive the backward reaction for completion. (A) 3 moles (B) 5 moles (C) 8 moles (D) 2 moles WORK SHEET - 01 CHEMICAL EQUILIBRIUM
Q.8 Ammonia at a pressure of 5 atm and H2 S gas at a pressure of 10 atm are introduced into an evacuated vessel. NH4HS (s)  NH3 (g) + H2 S (g) Kp = 62.5 atm2 The total pressure of gases after long time is : (A) 15 atm (B) more than 15 atm (C) less than 15 atm (D) unpredicted Q.9 The progress of reaction :A(g) xB(g) + yC(g) with time is presented in figure. What is the value of KC o at 300 K. 0.5 1.0 1.5 2.0 2.5 3.0 [B] [A] t (in sec) conc. (M) (A) 1 (B) 2 (C) 3 (D) 4 Q.10 Consider followingreactions in equilibrium with equilibrium concentration 0.01 M of everyspecies (I) PCl5 (g)  PCl3 (g) + Cl2 (g) (II) 2HI(g)  H2 (g) + I2 (g) (III) N2 (g) + 3H2 (g)  2NH3 (g) Extent of the reactions taking place is: (A) I > II > III (B) I < II < III (C) II < III < I (D) III < I < II Q.11 A definite amount of solid NH4HS is placed in a flask already containing ammonia gas at a certain temperature and 0.50 atm pressure. NH4HS decomposes to give NH3 and H2 S and at equilibrium total pressure in flask is 0.84 atm. The equilibrium constant for the reaction is : (A) 0.30 (B) 0.18 (C) 0.17 (D) 0.11 Q.12 At certain temperature (T) for the gas phase reaction 2H2O(g) + 2Cl2 (g)  4HCl(g) + O2 (g) Kp = 12 × 108 atm If Cl2 , HCl & O2 are mixed in such a manner that the partial pressure of each is 2 atm and the mixture is brough into contact with excess of liquid water. What would be approximate partial pressure of Cl2 when equilibrium is attained at temperature (T)? [Given : Vapour pressure of water is 380 mm Hg at temperature (T)] (A) 3.6 ×10–5 atm (B) 10–4 atm (C) 3.6 ×10–3 atm (D) 0.01 atm Q.13 A vessel of 250 litre was filled with 0.01 mole of Sb2 S3 and 0.01 mole of H2 to attain the equilibrium at 440°C as Sb2 S3 (s) + 3H2 (g)  2Sb (s) + 3H2 S (g). After equilibrium the H2 S formed was analysed bydissolvingit in water and treating with excess of Pb2+ to give 1.195 g of PbS (Molecular weight = 239) precipitate. What is value of Kc of the reaction at 440°C? (A) 1 (B) 2 (C) 4 (D) None of these
Q.14 For the following Equilibria : H2O (l)  H2O(g)  PK 2OHP where P 2OH  Vapour pressure of H2O(g) By which of the following ways P 2OH can be changed (A) By adding more H2O(l) (B) By adding more H2O(g) (C) Bychanging temperature (D)All of the above Q.15 For the reaction :A(s) B(g) + C(g) .What will be the value of natural logarithm of ratio of total pressure at 400K to that at 300K          300 400 P P ln if H = 16.628 kJ. (Given : R = 8.314J/K-mole) (A) 5/3 (B) 5/6 (C) 3/5 (D) 6/5 Q.16 At a equilibrium pressure of 3.3 atm N2O4 undergoes 10% decomposition to NO2 .At same temperature what will be equilibrium pressure required for 20% dissociation. (A) 3.3 atm (B) 6.6 atm (C) 4 atm (D) 0.8 atm [PARAGRAPH TYPE] Paragraph for question nos. 17 to 19 Following reaction is at equilibrium in basic medium at 300 K. I 2 (s)  I – (aq.) + IO– 3 (aq.) Equilibrium concentration at 300 K are , [ I– ] = 0.1 M, [IO– 3 ] = 0.1 M Given : G°f (I– , aq) = – 50 kJ/ mol G°f (IO– 3 , aq) = – 123.5 kJ/ mol G°f (H2O, l ) = – 233 kJ/ mol G°f (OH– , aq ) = – 150 kJ/ mol R = 3 25 J mol–1 K–1 log10 e = 2.3 Q.17 G° of the reaction in KJ mol– is (A) – 150.7 (B) – 172.5 (C) 172.5 (D) 150.7 Q.18 Valueofequilibrium constant is (A) 1025 (B) 1035 (C) 1030 (D) 1027 Q.19 pH valueat equilibrium is (A) 8 (B) 6 (C) 9 (D) 5
Paragraph for question no. 20 to 22 AccordingtoLeChatelierprinciplewhenanequilibriumissubjectedtoanyexternalchange,theequilibria/ reaction shiftsto compensate the effectof the change. Thisprinciple helps in shiftingthe reaction towards appropriate directions so as to increase % yield of any reaction. Q.20 Which of the following changes can not cause an increase in extent of dissociation of CH3COOH in its aqueous solution as per the reaction, CH3COOH(aq) + H2O  CH3COO ̄(aq) + H+ (aq) (A)Addition of water into the solution (B)Addition of NaOH into the solution (C)Addition of HCl into the solution (D) Removal of CH3COO ̄ from the solution. Q.21 A,B,C & D are in equilibrium in a 2 litre container at 400 K & their moles are respectively 4, 5, 8 & 6. If the reaction involved is 3A(g) + 2B(g)  C(g) + 5D(g) then calculate equilibrium concentration of C when volume is increased to 10 litre. (A) 4M (B) 0.8 M (C) 5 M (D) None of these Q.22 If it is given that conversion of graphite to diamond in an endothermic reaction & the conversion C(graphite)  C(diamond) attains equilibria at 1.5 ×109 Pa at 300 K then comment at what pressure equilibria can be attained at 500 K. (A) P > 1.5 × 109 Pa (B) P < 1.5 × 109 Pa (C) P = 1.5 × 109 Pa (D)At any pressure Paragraph for question nos. 23 to 25 In a closed rigid vessel, N2 and H2 gases are taken in 9 : 13 mole ratio, bywhich the following equilibria are established : N2 (g) + 3H2 (g) 2NH3 (g) ; P1 K = ? N2 (g) + 2H2 (g) N2H4 (g) ; P2 K = ? At equilibrium, the total pressure is 14 atm, the partial pressure of ammonia is 2 atm and the partial pressure of hydrogen is 4 atm Q.23 The value of P1 K is : (A) 80 1 atm2 (B) 2 atm 80 1  (C) 80 atm2 (D) 2 atm 40 1  Q.24 The value of P2 K 1 is : (A) 2 atm 80 3  (B) 2 atm 3 80 (C) 2 atm 3 40 (D) 2 atm 3 5  Q.25 The equilibrium partial pressure of N2 is : (A) 5 atm (B) 7 atm (C) 3 atm (D) 2 atm