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1 Test ate: 8..5 (Saturday) Test Time: 9:5 M to :5 M Test Venue: Lajat hawan, Madhya Marg, Sector 5-, handigarh r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

2 r. Sangeeta Khanna Ph. TEST TE: 8..5 RE THE INSTRUTIONS REFULLY. The test is of hour duration.. The maximum marks are.. This test consists of 6 questions.. Kee Your mobiles switched off during Test in the Hall. Section (Single nswer) Negative Marking [-] This Section contains 5 multile choice questions. Each question has four choices ), ), ) and ) out of which ONLY ONE is correct. (Mark only One choice) 5 = Marks. The incorrect statement includes that a. G can have a negative sign when log K > b. When G is ositive, equilibrium is shifted in the direction of the reverse reaction c. When G is ositive, the yield of the roducts of the forward reaction is comaratively small d. When K >, the equilibrium is shifted to the direction of the reverse reaction.. In a certain exeriment a student finds that the H of. M solution of three otassium salts KX, KY and KZ are 7., 9. and. resectively. Then the correct order of increasing acid strength of the acid is a. HX < HY < HZ b. HZ < HX < HY c. HY < HX < HZ d. HZ < HY < HX. The weak monorotic acid H is.% dissociated in.86 M solution. What is the acidity constant, Ka, of H? a..8 b c.. d..5. Which of the following grahs show the change in H of cm and of M NaOH when M sulhuric acid is added? H H a. b. 7 7 Volume of acid added/cm Volume of acid added/cm H c. d. 7 H 7 Volume of acid added/cm Volume of acid added/cm r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

3 r. Sangeeta Khanna Ph. 5. The osition of equilibrium lies to the right in each of these reactions: N H5 NH NH NH : NH Hr NH r ; NH Hr NH5 ased on this information, what is the order of acid strength? 5 Hr a. Hr NH5 NH b. N H5 NH NH c. NH > N H > r d. N H NH 6. HOOH and H OOH solutions have equal H. If K /K (ratio of acid ionization constants) is, their molar concentration ratio will be: a. b..5 c. d..5 Sol. K K H + = K K = K K.5 K 7. What will be the result if ml of.6 M Mg(NO ) is added to 5 ml of.6m Na O? [The Ks of Mg O (s) equals 8.6 x 5 ] a. No reciitate will form b. reciitate will form and an excess of Mg + ions will remain in the solution c. reciitate will form and an excess of O ions will remain in the solution d. reciitate will form but neither ion is resent in excess 8. For the reaction, Pl (g) + l (g) Pl 5 (g), the value of K at 5 is.6 atm. The value of K at this temerature will be: a. 5 (mol/l) b. 6 (mol/l) c. 5 (mol/l) d. 5 (mol/ L) Sol. K = K c (RT) n.6 = K c (.8 5) Or K c = 6.9 (mol/l) 9. XY dissociates as: XY (g) XY(g) + Y(g) When the initial ressure of XY is 6 mm Hg, the total equilibrium ressure is 8 mm Hg. alculate K for the reaction assuming that the volume of the system remains unchanged: a. 5 b. c d. Sol. XY (g) XY(g) Y(g) Initial t eqbm 6 6 P Total ressure = = 8 nm P K 6. For the reaction, (g) + (g) (g), the equilibrium artial ressures are P =.5 atm, P =. atm and P =. atm. The value of the ressure was so reduced that after attainment of equilibrium again, the artial ressure of & were doubled. The artial ressure of would be r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE r a.. atm b..6 atm c.. atm d..8 atm

4 r. Sangeeta Khanna Ph.. Sol. K = =.5. gain = or =. atm... Starting with one mole of O and two moles of SO, the equilibrium for the formation of SO was established at a certain temerature. If V is the volume of the vessel and x is the number of moles of SO resent, the equilibrium constant will be a. x V ( x) b. x ( x)( x) Sol. SO + O SO Initial moles mole t eqm. ( x) ( x) x = ( x) Molar conc. ( x)/v ( x)/v x/v K= (x / V) ( X) V (- x) V x V ( x) c. ( x) V d. x ( x)( x). The H of M ammonium acetate solution will be (Given K a of acetic acid =.76 and K b of NH OH =.75) a. 7.5 b c. 8. d Sol. For salt of weak acid, weak base, H = 7 + [Ka K b ] = 7 + (.76.75) = 7.5. Which of the following secies is more soluble in water? a. M(OH), (K s = 5 ) b. M(OH), (K s = 5 ) b. MOH, (K s = 5 ) d. ll have same solubility K Sol. S of M (OH) = s K S of M (OH) = s ; S of MOH Ks. The molar solubility (in mol L ) of a saringly soluble salt MX is s. The corresonding solubility roduct is given by K s. S is given in terms of K s by the relation: a. s = (K s /8) / b. s = (8 K s ) / c. s = (56 K s ) /5 d. s = (K s /56) /5 Sol. MX M + + X K s = [M + ] [X ] = (S) (S) = 56 S 5 Or K s S 56 / 5 r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

5 r. Sangeeta Khanna Ph. 5. The solubility of solid silver chromate, g ro is determined in three solvents: Substance K s g ro 9 x I. Pure water II.. M gno III.. M Na ro IV. NH solution Predict the relative solubility of g ro, in the three solvents: 6. a. I = II = III = IV b. I < II < III < IV c. II = III < I < IV d. II < III < I < IV K a, K a and K a of H PO are resectively x, y and z, H of. M Na HPO solution is Sol. x y a. b. HPO is amhirotic and it involves HPO H + + PO K a and y z c. K a x y z d. r. Sangeeta Khanna Ph. 5 HEMISTRY OHING IRLE K a k a HPO + H + H PO For such cases K a K H = a y z 7. In each of the following total ressure setu at equilibrium is assumed to be equal and is atm with equilibrium constants K given I : ao (s) ao(s) + O (g), K II : NH HS(s) NH (g) + H S(g), K III : NH O NH (s) NH (g) + O (g), K In the increasing order a. K = K = K b. K < K < K c. K < K < K d. None of these Sol. I : ao (s) ao(s) + O (g) x O x x K = = K K = II : NH HS(s) NH (g) + H S(g) NH HS x x x x x x K = NH. H S K K =.5 III : NH O NH (s) NH (g) + O (g), x x x NH x

6 r. Sangeeta Khanna Ph. HS x x K = NH H S K 7 K =.8 Thus, K < K < K 8. onsider following equilibria at K and K with their equilibrium constants K K I : (g) (g) K eq = K eq = 5 II : (g) (g) K eq = K eq = 5 Thus, a. I is endothermic, II is exothermic b. I is exothermic, II is endothermic c. I and II both are endothermic d. I and II both are exothermic 9. If the E cell for a given reaction has a negative value, which gives the correct relationshi for the values of G and K eq? a. G > ; K eq < b. G > ; K eq > c. G < ; K eq > d. G < ; K eq <. mol each of and and mol each of and are laced in L flask, if equilibrium constant is.5 for + +, equilibrium concentrations of and will be in the ratio a. : b. : c. : d. : Sol. + + Initial [][] Reaction quotient before equilibrium is attained = 9 K (.5) [][] Thus, reaction shifts in backward side + + Initial Equil. ( x) ( x) ( + x) ( + x) K K.5 ( x) ( x) x x.5 x =.6 [] x.6 [] ( x).. onsider the following reactions (in gaseous hase) in equilibrium with equilibrium concentrations. M of every secies (I) SO + O SO ; (II) N + H NH (III) N O NO ; (IV) NO + 6H O NH + 5O ; Extent of reaction will be in order a. I = II III = IV b. I = II = III < IV c. III < I = IV < II d. IV < III < I < II Sol. Equilibrium concentration is. M in each case. alculate K c in each case. Greater the value of K c, greater the extent of reaction. r. Sangeeta Khanna Ph. 6 HEMISTRY OHING IRLE

7 r. Sangeeta Khanna Ph.. The enthaly of atomization of grahite is 75 kj mol and that of hydrogen is 8 kj mol. The enthaly of formation of methane is -76 kj mol. The enthaly of formation of the H bond from gaseous carbon and atomic hydrogen is a. +8 kj b. +55 kj c. -55 kj d. -8 kj Sol. gr + H H H f = - 76 H =.E (Reactant).E (Product) = [75 + 8] E = - 76 = 597 E E = 8 E. Which of the following salts shall cause maximum cooling when one mole of the salt is dissolved in the same amount of water: (Integral heat of solution at 5 is given below for each solute). a. KNO (H = 5. KJ) b. Nal (H = 5.5 KJ) c. KOH (H = KJ) d. Hr (H = -8. KJ) Sol. salt with maximum H solution will cause maximum cooling. Given NH (g) + l (g) Nl (g) + Hl (g); H N (g) + H (g) NH (g) ; H H (g) + l (g) Hl (g); H The heat of formation of Nl (g) in the terms of H, H and H is: a. H H H H f b. H H H H f H c. H H H f d. None Sol. im : N l Nl Oerate Eqn. (ii) Eqn.(i)- Eqn.(iii) We get H ( H ) ( H ) H H H H H H H H. f 5. Which one of the following is NOT a state function? a. heat b. ressure c. temerature d. enthaly 6. H f (O ) (g) = -9 kj mol H f (H O) (l) = -86 kj mol H f (H ) (g) = -7. kj mol The standard enthaly change in kj mol at 98 K for the reaction H (g) + O (g) O (g) + H O (l) is the value of a (86) + 7 b. -9 -(86) - 7 c (86) + 7 d (86) If the value of G for a reaction is negative, this shows that a. an increase in temerature will favour the formation of roducts. b. the concentration of reactants will be greater than that of roducts at equilibrium c. H for the reaction is also negative d. the equilibrium constant for the reaction is greater than. r. Sangeeta Khanna Ph. 7 HEMISTRY OHING IRLE

8 r. Sangeeta Khanna Ph. 8. Which one of the following would cause the reciitation of more silver in the equilibrium g + (aq) + Fe + (aq) g(s) + Fe + (aq) H = - Q? a. warming under increased ressure b. removing some of the solid silver reciitated c. increasing the concentration of Fe + ions d. increasing the concentration of Fe + ions 9. Out of molar entroy (I), secific volume (II), heat caacity (III), volume (IV), extensive roerties are: a. I, II b. I, II, IV c. II, III d. III, IV. etermine which of the following reactions at constant ressure reresent surrounding that do work on the system environment I. NH (g) + 7O (g) NO (g) + 6H O(g) II. O(g) + H (g) H OH() III. (s, grahite) + H O(g) O(g) + H (g) IV. H O(s) H O() a. III, IV b. II and III c. II, IV d. I and II, IV Sol. w = -P ext, V = - n g RT and n g is ve for I and III also V = -ve for IV (on contraction surrounding does work on surrounding).. t 5, a. mole samle of a gas is comressed in volume from. L to. L at constant temerature. What is work done for this rocess if the external ressure is. bar? a..6 J b. 8. J c.. J d.. J. given mass of gas exands from the state to the P state by three aths, and as shown in the figure. If w, w and w resectively be the work done by the gas along three aths then: a. w > w > w b. w < w < w c. w = w = w V d. w < w < w. For the reaction: FeO (s) FeO(s) + O (g); H = 8.8 kj at 5, what is (E or U) at 5? a. 8.8 kj b. 8. kj c kj d kj Sol. H = E + n g RT = E + E = 8. kj. Given the following equations and H values, determine the enthaly of reaction at 98 K for the reaction: H (g) + 6F (g) F (g) + HF (g) H (g) + F (g) HF(g); H 57 kj (s) + F (g) F (g); H = - 68 kj (s) + H (g) H (g); H 5 kj a. 65 b. 86 c d r. Sangeeta Khanna Ph. 8 HEMISTRY OHING IRLE

9 r. Sangeeta Khanna Ph. Sol. H = H H H 5. How much electrical work will be done in the following Redox reaction If. V ;.8 V / / a. 8 kj b. kj c. 6 kj d. 5 kj Sol. E cell Ecathode Eanode = +.8. =.6 volt Electrical work = nfe cell = J =.6 kj SETION (ssertion & Reason) Negative Marking [-] This Section contains multile choice questions. Each question has four choices ), ), ) and ) out of which ONLY ONE is correct. (Mark only One choice) = Marks () If both () and (R) are correct and (R) is the correct exlanation for (). () If both () and (R) are correct but (R) is not the correct exlanation for (). () If () is correct, but (R) is incorrect. () If both () and (R) are incorrect.. ssertion: For a articular reaction, heat of combustion at constant ressure (q ) is always greater than that at constant volume (q v ). Reason: ombustion reactions are invariably accomlished by increase in number of moles. a. () b. () c. () d. (). ssertion: The H of an aqueous solution of acetic acid remains unchanged on the addition of sodium acetate. Reason: The ionization of acetic acid is not affected by the addition of sodium acetate. a. () b. () c. () d. (). ssertion: mixture of NH OH and NH l forms a buffer solution. Reason: buffer solution reacts with small quantities of hydrogen or hydroxyl ions and kees the H almost same. a. () b. () c. () d. (). ssertion: On mixing 5 ml of 6 M a + ion and 5 ml of -6 MF ion, the reciitate of af will be obtained K s (af ) = 8. Reason: If K s is greater than ionic roduct, reciitate will be obtained. a. () b. () c. () d. () Sol Ionic roduct = 8 K s > ionic roduct no t 5. ssertion: The aqueous solution of H OONa is alkaline in nature Reason: cetate ion undergoes anionic hydrolysis. r. Sangeeta Khanna Ph. 9 HEMISTRY OHING IRLE

10 Pressure (mm of mg) r. Sangeeta Khanna Ph. a. () b. () c. () d. () 6. ssertion: Heat and work are ath deendent. Reason: Heat is organised form & work is random form of energy. a. () b. () c. () d. () 7. ssertion: There is no change in internal energy of an ideal gas on exansion at constant temerature. Reason: Internal energy of an ideal gas is a function of temerature only. a. () b. () c. () d. () 8. ssertion: H of H OOH(.M) increases on dilution. Reason: Increase in H is due to increase in concentration of (H + ) on dilution. a. () b. () c. () d. () 9. ssertion: The heat absorbed during the isothermal exansion of an ideal gas against vacuum is zero. Reason: No work will be done by the gas under this condition a. () b. () c. () d. (). ssertion: H and E are the same for the reaction, N (g) + O (g) NO(g), Reason: This mixture is a Homogeneous system. a. () b. () c. () d. () SETION (Paragrah Tye) Negative Marking [-] This Section contains aragrahs. Each of these questions has four choices ), ), ) and ) out of which ONLY ONE is correct. = Marks Passage ehydration of salts is an imortant class of heterogeneous reactions. The salt hydrates during dehydration often dissociates in stes to form a number of intermediate hydrates according to the revailing ressure of moisture in contact with the solid hydrates. Thus coer sulhate entahydrate on dissociation yields trihydrates, monohydrates and then the anhydrous salt in the above order as follows: uso.5h O uso. H O H O 7.8 uso.h O uso. H O uso.h O uso H O.8. What is the ratio of equilibrium constants K for the [uso 5H O uso H O] and [uso H O uso ] a b..765 c d H O Moles of water/moles of uso 5.6 r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

11 r. Sangeeta Khanna Ph. 6.8 Sol. Ratio of K = = Which of the following condition is favourable for dehydration of uso. 5H O? a. Low humidity in air b. High temerature c. High ressure d. Low humidity in air and High temerature Sol. ehydration of uso. 5H O favourable at low humidity in air, high temerature Passage The equation for the equilibrium is a. + + b. + c. + d. +. The value of the K c for the equilibrium is a..78 b.. c..77 d.. SETION (One or More than One nswer Tye) No Negative Marking This Section contains multile choice questions. Each question has four choices ), ), ) and ) out of which One or MORE THN ONE NSWER is correct. 5 = 5 Marks. Identify the state functions from the following: a. Heat b. Work c. Enthaly change d. Internal energy change,. n adiabatic rocess is one in which : a. energy is transferred as heat b. no energy is transfer as heat c. U = w d. the tem. of gas increases in a reversible adiabatic comression,,. H < E for the reaction: a. N (g) + H (g) NH (g) b. g O(s) g(s) + O (g) c. O(g) + O (g) O (g) d. (s) + O (g) O (g) r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

12 r. Sangeeta Khanna Ph., Sol. H = E + n g RT; H < E if ng = -ve. Which of the following affect the heat of reaction? a. Physical states of reactants and roducts b. llotroic forms of elements c. Temerature d. Reaction carried out at constant ressure or constant volume,,, Sol. (a) H O (l) has different H than H O(g) (b) (diamond) has different H c than that of grahite. (c) is correct H will change with change in temerature because heat caacity varies with temerature. (d) is correct because w is different at constant ressure or constant volume. When solids and liquids are i nvolved difference is negligible but if gases are involved difference is more. 5. When one mole of a gas is exanded isothermally and reversibly at K from a volume of L to L then: a. The work done in the exansion is.79 kj mol b. hange in enthaly equal to.79 J mol c. hange in enthaly equal to zero d. The work done in the exansion is zero, Sol. (a) is correct. w RT V ln V. 8. log 79 Jmol.79 kj mol (b) is incorrect because H = E + PV = E + RT = Which among the following statements is/are correct? a. H = - log (H O + ) b. H decreases with increase of temerature c. H cannot be zero, negative or more than d. If a solution of strong cid is diluted ten times, its H increases by,, 7. hoose the correct statement(s): a. H of an acidic buffer increases if more salt is added. b. H of a basic buffer decreases if more salt is added. c. In a saturated solution, ionic roduct is equal to its solubility roduct d. The term solubility roduct is only for saringly soluble salts.,, Sol. cidic uffer H Ka log Salt cid asic uffer Salt H = - Kb log ase 8. The salts whose aqueous solutions have H less than 7 are a. uso b. Lil c. Na O d. KNO r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

13 r. Sangeeta Khanna Ph., Sol. uso and Lil are salts of strong acid and weak base. Their solutions are acidic with H < Which of the following is correct? a. catalyst lowers the activation energy barrier for the forward and reverse reaction b. catalyst increases the rate constant for backward and forward reaction c. For endothermic reaction increasing the temerature increase the rate constant of forward reaction more than backward reaction d. For endothermic reaction increasing the temerature increase the rate constant for backward and forward reaction in equal ratio,, Sol.(a), (b) and (c) are correct and (d) is incorrect answer. Which of the following are acid-base conjugate airs? a. HO, and O b. NH and NH c. Hl and l d. H O + and OH SETION E (Matrix Tye) No Negative Marking This Section contain question. Each question has four choices (,, and ) given in olumn I and five statements (, q, r, and s) in olumn II. ny given statement in olumn I can have correct matching with one or more statement(s) given in olumn II. 8 = 8 Marks. Match olumn I with olumn II olumn I olumn II () Reversible cooling of an ideal gas at constant volume (P) w = ; q < ; U < () Reversible isothermal exansion of an ideal gas (Q) w < ; q > ; U > () diabatic exansion of non-deal gas into vacuum (R) w = ; q = ; U = () Reversible melting of sulhur at normal melting oint (S) w < ; q > ; U = Sol. () P; () S; () R; () Q r. Sangeeta Khanna Ph. HEMISTRY OHING IRLE

Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY COACHING CIRCLE D:\Important Data\2016\+1\Physical\Test\Grand Test\GT-6\Obj-Chemical & Ionic Equilibrim

$Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY COACHING CIRCLE D:\Important Data\2016\+1\Physical\Test\Grand Test\GT-6\Obj-Chemical & Ionic Equilibrim$ r. Sangeeta hanna Ph. EMISTRY OING IRLE :\Important ata\06\+\physical\test\grand Test\GT-6\Obj-hemical & Ionic Equilibrim 0..07.docx r. Sangeeta hanna Ph. RE INSTRUTIONS REULLY. The test is of hours duration..