SOLUTIONS TEST SERIES-NEET [(4+1)(4+1)(+10)] PART TEST - XII/01 PART - I : PHYSICS 1. 8. q 4 = 6 ´10 D i i Þ Vd = Þ Vd µ neA A rr p.r k pr cos q (4) V = k 3. (2) As water droplet is at rest ur So, F net = 0 r 3 = =k r3 p cos q r2 4. 5. 6. 4.9 ´ 105 mg Þ q = 2 × 10–9 C (3) Work done on equipotential surface is zero. (4) (3) For series combination, Þ 9. i1 = Þ æC ö CS èç 2 ø÷ 1 = = = 1: 4 Cp = C + C Þ Cp = 2C Þ Cp 2C 4 10. = 9 ´109 ´ (Here, K = 9 × 109) e2 11. 2 (1.6 ´10-19 )2 (1.6 ´10 -10 2 ) = 9 ´10-9 N -9 \ Acceleration of electron = F = 9 ´ 10 me 9 ´ 10-31 = 10–9 × 10+31 = 1022 m/s2 6 ´ i where i is the current delivered by the battery.. 9+ 6 2 ´ 15 = 5A 6 Thus, potential difference across 2W resistor is V = iR = 5 × 2 = 10V (1) For conductors KQ KQ ; V (r < R ) = R R So, potential inside the surface is same as the potential on surface. So statement (I) is correct. ur s Just outside the surface of conductor, E = nˆ 2e 0 nĚ‚ = unit vector perpendicular to surface So, statement (II) is also correct. (1) Given : emf e = 2.1 V I = 0.2 A, R = 10W Internal resistance r = ? From formula. e – Ir = V = IR 2.1 – 0.2r = 0.2 × 10 0.1 2.1 – 0.2 r = 2 or 0.2 r = 0.1 Þ r = = 0.5 W 0.2 V (r = R ) = (4) Force of mutual attraction between the electron and proton is r Þ V = 18V \ i= C Þ F = 9 ´ 109 ´ V2 V2 Þ 36 = R 9 Current through the 9W resistor is i1 = Cp r2 (3) We have, P = V 18 = = 2A R 9 The 9W and 6W resistors are in parallel, therefore CS Ke 2 B q 2 = -2 ´10 -8 C V = k ´ 3 ´ 10 -8 = 9 ´ 10 9 ´ 3 ´ 10 -8 volt = 27 × 10 = 270 V For parallel combination, F= -8 C q 3 = -3 ´10 C 2 = 1m 2 q \ Potential at the centre O, V = k r é 2 ´ 10-8 -2 ´ 10-8 -3 ´ 10-8 6 ´ 10-8 ù V = kê + + + ú 1 1 1 1 êë úû 1 1 1 = + Þ C =C S CS C C 2 7. = 2m \ DO = OB = AO = OC = V=0 C : PT - XII/01 O qE C C A q 1 = 2 ´10 -8 C 0.1 ´ 10 -3 ´ 9.8 C -8 . mg Þ mg = qE Þ q = E Þq= ( 2 )2 + ( 2 )2 (1) AC = BD = (3) i = neAVd 2. TEST CODE 2 12. NEET PT - XII/01 (3) Given, Dipole moment, p = q × l Resistance at 0°C, R0 = 2 W q= Resistance at 80°C, 6.8 W 20. Using R = R0(1 + aDT) p 4 ´10-5 = = 2 ´ 10-3 C = 2mC 0.02 l R1 = 2W (4) where a is the thermal coefficient of resistance R 3 = 6W R 4 = 8W \ 6.8 = 2{1 + a(80 – 0)} X 6.8 – 1 = a ´ 80 Þ 2 R 2 = 4W 3.4 – 1 2.4 = = 0.03 Þ a= 80 80 Net Resistance = 13. \ a = 3 × 10–2 °C–1 (3) Flux does not depend on the size and shape of the close surface, and so, it remains same. 14. (2) U = 15. (3) Assertion: In non-polar molecule, centre of +ve charge coincides with centre of –ve charge, hence net dipole moment is zero. Reason: When non-polar material is placed in external field, centre of charges does not coincide, hence give non-zero moment in field. 1 é q 2 Qq Qq ù + ê + ú=0 4p Î0 ë a a 2a û 2q . \ Q=(2 + 2) kp and Ee = 3 ; \ Ea = 2Ee r r 17. (3) Resistance r2 and r 3 are in parallel so potential difference across r 2 = r3 = V 16. (2) We have Ea = \ i 2 r2 = i3 r3 Þ i 2 = 2kp 3 i3r3 r2 ... (i) i r \ 3= 2 i1 r2 + r3 18. (4) Charge mobility V (m) = d [ Where Vd = drift velocity ] E E EA I(r) and resistivity (r ) = j = I Þ E = A 21. = 19. ) 2 m2 Þ m = 1.0 Vs 5 ´ 1.7 ´10 –8 r r r (4) Torque, t = p ´ E = pE sin q 4 = p × 2 × 105 × sin 30° 4 = 4 ´ 10-5 Cm or, p = 5 2 ´ 10 ´ sin 30° 1 1 2´ 4 46 + +6+8 = + 14 = W 2 4 2+4 3 (1) In ohm's law, we check V = IR where I is the corrent flowing through a resistor and V is the potential difference across that resistor. Only option (a) fits the above criteria. Remember that ammeter is connected in series with resistance and voltmeter parallel with the resistance. 22. (1) Resistance offer obstruction to current while conductance allow electric current to flow, so conductance is the reciprocal of resistance. dV = 8x 23. (4) V = 5 + 4x 2 \ ...(i) dx Force on a charge is æ dV ö F = qE = q ç - ÷ = q ( -8x ) ; from (i) è dx ø = -2 ´ 10- 6 ´ (–8 ´ 0.5) = 8 ´ 10 -6 N 24. (2) For the system to be in equilibrium, net force on each of the charges must be zero. Net force on any of – Q to be zero, we have –Q –Q 2k Q2 Q 2 kQq +k 2 - 2 =0 2 2a a 2 Q \ q= q Q (1 + 2 2) 4 –Q 25. V VA Þ m= d = d E Ir ( 1 1 + + R3 + R 4 R1 R 2 = ær ö Current i1 = i2 + i3 Þ i1 = ç 3 + 1÷ i3 è r2 ø 1.1 ´10 –3 ´ p ´ 5 ´10 –3 Y 26. a –Q (2) Under the effect of applied electric field, the free electrons get accelerated due to electric field and they move from lower to higher potential. However, electron collides with lattice ion during passage and follow curved path. (3) We know that potential energy of discrete system of charges is given by 1 æ q1q 2 q 2 q 3 q 3 q1 ö ç ÷ + + 4p Î0 çè r12 r23 r31 ÷ø According to question, 1 æ q1q 2 q 2 q 3 q 3 q1 ö + + ç ÷ Uinitial = 4p Î0 è 0.3 0.5 0. 4 ø U= NEET PT - XII/01 Ufinal = 28. Q 2 Q ærö 1 4 4pR 2 So, = q = ´ ç ÷ = 64 ´ = q èRø s smaller 16 1 4 pr 2 33. (4) Kirchhoff's first law is based on conservation of charge and Kirchhoff's second law is based on conservation of energy. 1 Q 1 æ -2Q ö 34. (1) V = V1 + V2 + V3 = . + ç ÷ 4p Î0 R 4p Î0 è R ø 1 æ q1q 2 q 2 q 3 q 3 q1 ö + + ç ÷ 4p Î0 è 0.3 0.1 0. 4 ø Uf – Ui = 27. 3 sbigger 1 æ q 2 q 3 q 2q 3 ö q3 (8q 2 ) çè ÷ø = 4 p Î0 0.1 0.5 4p Î0 (4) Net Power, P = 15 × 45 + 15 × 100 + 15 × 10 + 2 × 1000 = 15 × 155 + 2000 W P Power, P = VI Þ I = V 15 ´155 + 2000 \ I main = = 19.66 A » 20 A 220 35. æ e ö (4) i = ç ÷ èR+rø Power delivered to R. 2 æ e ö P = i2R = ç ÷ R è R+r ø dP =0 P to be maximum, dR 36. m = 9.1 ´ 10-31 1 CV¢2 ´ 2 2 = CV¢2 = 900 × 10–12 × 25 × 102 = 225 × 10–8 = 2.25 × 10–6 J 30. (3) 31. (1) In series 2E is = 2r + 2 In parallel E E 2E = r r +4 +2 2 as, is = ip 2E 2E = 2r + 2 r + 4 Þ r = 2W Þ E r R E r E r r 38. 39. 40. 41. ip R (2) From law of conservation of charge qi = q f Q 4 4 = 64 and, pR 3 = 64 ´ pr 3 3 3 q r 1 Þ R = 4r Þ = R 4 Þ 64q = Q Þ r r since angle between E and P is 180° is ip = 32. (3) r = -19 2 -15 28 ne 2 t 8.5 ´10 ´ (1.6 ´10 ) ´ 25 ´ 10 = 10–8 W-m 37. (3) Potential energy of electric dipole in external electric field rr U = - P.E = -PE cos q = - PE cos180° 2 d éæ e ö ù êç or ÷ R ú = 0 or R = r dR êè R + r ø ú ë û 29. (2) By conservation of charge qi = qf Þ C × 100 = CV¢ + CV¢ Þ V¢ = 50 V So, Uf = 1 æ 3Q ö 1 æ 2Q ö Q çè ÷ø = çè ÷ = 2pÎ R ø 4p Î0 R 4p Î0 R 0 rl (3) Resistance, R = A l l rl 2 [Q Volume (V) = Al.] R =r ´ = A l V Since resistivity and volume remains constant therefore % change in resistance DR 2Dl = = 2 ´ (0.5) = 1% R l + \ U = +PE On moving towards right electric field strength decrease \ U decreases. Net force on electric dipole is towards right and net torque acting on it is zero so move towards right. (4) (3) Capacitance will increase but not 5 times (because dielectric is not filled completely). Hence, new capacitance is greater than 100 µF and less than 500 mF. (4) (2) Net resistance of the circuit, Req = 2 W + 1 W + 7 W = 10 W Net Voltage, Vnet = 10 – 5 = 5 V Using Kirchhoff’s law Vnet 5 i = R = 10 = 0.5 A eq 4 42. NEET PT - XII/01 R1 (3) R1 + R2 = 1000 Þ R2 = 1000 – R1 On balancing condition R1(100 – l) = (1000 – R1)l ...(i) (l ) On Interchanging resistance balance point shifts left by 10 cm. On balancing condition (1000 – R1) (110 – l) = R1 (l – 10) or, R1 (l – 10) = (1000 – R1) (110 – l) Dividing eqn (i) by (ii) 1000 \ Efficiency = 1000 + P ´ 100 = 96%. loss G 100 – l 44. Current, i = 100 - l l = G l - 10 110 - l Þ (100 – l) (110 – l) (100 – l + 10) (l – 10) = l(l – 10) =(110 – l) Þ 11000 – 100l – 110l + l2 = l2 – 10l Þ 11000 = 200l or, l = 55 Putting the value of ‘l’ in eqn (i) R1 (100 – 55) = (1000 – R1) 55 Þ R1 (45) = (1000 – R1) 55 Þ R1 (9) = (1000 – R1) 11 Þ 20 R1 = 11000 \ R1 = 550 W (3) Let P is the observation point at a distance r from –2q and at (L+r) from +8q. Given now, net EFI at P = 0 r \ E1 = EFI (Electric Field Intensity) at P due to +8q r E 2 = EFI (Electric Field Intensity) at P due to – 2q 4 1 uur uur k(8q) k(2q) \ = 2 E1 = E 2 = 2 \ 2 2 + (L r) (r) (L + r) r 2 2 4r = (L+r) Þ 2r = L+r r=L \ P is at x = L + L = 2L from origin )dt 0 ö 8 3 3 ÷ + (15 - 0 ) ø 3 1 Q (if r ³ R) 4p Î0 r 2 Electric field at a distance 15 cm from the centre of sphere will be E= E= 9 ´ 109 ´ 3.2 ´ 10 -7 = 0.128 ´ 106 = 1.28 ´ 105 N/C 225 ´ 10 -4 PART - II : CHEMISTRY 51. (4) 1 æ a ö 1 æ 35 ö k = ln ç ln ç ÷= ÷ t è a – x ø 15 è 35 – 9 ø 1 æ 35 ö ln 15 çè 26 ÷ø (4) Solutions in which solute - solute and solvent-solvent interactions are almost similar to solute-solvent interactions are known as ideal solution. (2) A – (iv), B – (i), C – (ii), D – (iii) (3) For following reaction, 2NO (g) + O 2 (g) ® 2NO 2 (g) 1 Wh en the volume of vessel changes to then 3 concentration of reactant become three times. The rate of reaction for first order reaction µ concentration of reactant. So, rate of reaction increases three times. (1) Molality of solution does not depend on the temperature as it depends on the moles of solute and mass of solvent. Hence, both assertion and reason are true. K ´1000 ´ w 5.12 ´ 1000 ´ 1 (1) By using, M = f = DTf ´ WSolvent 0.40 ´ 50 = 256 g mol–1 2.303 RT 0.059 V 0 0 (3) Ecell = log K c or Ecell = log K c nF n 0.059V = log1016 = 0.4736 V 2 = 52. 53. 54. dF K = [4 - 2q] = 0 Þ q = 2 mC dq r 2 (3) From the Gauss's law q Q f = in = Q Q = CV Î0 Î0 55. R = 2W, V = 220 V P 1000 Current, I = = V 220 2 1000 æ ö ´2 Ploss = I 2 R = ç è 220 ø÷ 2 8(15)3 Þ q = 2250 + 9000 = 11250 C 3 50. (1) If the charge on a spherical conductor of radius R is Q, then electric field at distance r from centre is E=0 (if r Ð R) r2 For F to be maximum, 46. (2) For metals like copper, at temperature much lower than 0°C, graph deviates considerably from a straight line. 47. (4) Given : Power, P = 1 kW = 1000 W = Poutput ò (20t + 8t Þ q = 10 × (15)2 + Kq(4 - q) CV \f = Î0 15 15 (2) Let distance between the two divided charges be r. F= dq Þ ò dq = ò idt Þ q = dt æ 20t 2 8t 3 ö æ 152 - 02 + Þ q = çç ÷÷ = 20 ´ ç 3 ø0 2 è 2 è R1 From Coulomb’s law, force between two charge, 45. 48. (2) A - (ii); B - (iii); C - (iv); D - (i) 49. (2) Given, i = a0t + bt2 Put a0 = 20 and b = 8, we get i = 20t + 8t2 ...(ii) R2=1000 – R1 43. Pin = Poutput + Ploss R2 = 1000 – R1 56. 57. NEET PT - XII/01 5 58. (2) Higher the value of KH, lower is the solubility of gas, correct order : HCHO > CH4 > CO2 > Ar 59. (2) Ionic molar conductivity of H+ is very high and NH4OH is a weak electrolyte. 60. (2) Depression in freezing point is a colligative property and depends only on the amount of solute. DTf = kf .m 1 DT fx = DT fy k f × mx = k f × my 1 Mx 1 67. (4) Kohlrausch’s Law states that at infinite dilution, each ion migrates independently of its co-ion and contributes to the total equivalent conductance of an electrolyte a definite share which depends only on its own nature. From this definition we can see that option (4) is the correct answer. 68. (3) The rate of formation of SO3 will be equal to rate of disappearance of SO2. This is because stoichiometry is same. 69. 425.9 S cm2 mol–1 and L°m (NaA) = 100.5 S cm2 mol–1 My ° + + l° L°m (HA) = l H A 1 Þ 61. 62. 63. 64. = l ° + + l° 1 My = Þ Mx : My = 1 : 0.25 4 Mx + l° - + l ° a= 2a 2 2b Lm L 0m = Ka(CH3COOH) = 7.8 = 0.02 390 cα 2 cα × cα = 1– α c – cα 0.04 ´ (0.02)2 = 1.6 × 10– 5 1– 0.02 pKa = 4.79 Use: pKa + pKb = pKw = 14 Þ pKb = 14 – 4.79 = 9.21 = = 50 = 0.125 400 1000 g = 55.55 mole 18 g / mol nsolute 1 = nsolute + nwater (1 + 55.55) = 0.01768 = 0.0177 -1 litre time ) r 71. (4) Given [A] = 0.01 M Rate = 2.0 × 10–5 mol L–1 S–1 8r For a first order reaction; b 3 2a 2r Q For (1) and (3), the rate is doubled when conc. of G is doubled keeping that of H constant i.e., rate µ [G] \ x=1 From (2) and (3), y = 2 \ Overall order is 3. (2) a = L °m (HA) Mole fraction = [G]mole [H]mole rate(mole - L m (HA) Moles of 1 kg H2O = +3 1 Na + 70. (4) 1.00 m i.e., 1 mole of solute is present in 1 kg of water. ® MnO ( OH ) + NH 3 MnO 2 + NH +4 + e - ¾¾ (4) Overall order = sum of orders w.r.t each reactant. Let the order be x and y for G and H respectively litre b - l° k (HA) ´1000 5´10-5 ´1000 = Molarity of HA 0.001 = 50 S cm2 mol–1 litre a Cl- L °m (HA) = 425.9 + 100.5 – 126.4 = 400 S cm2 mol–1 k (HA) = 5 × 10–5 S cm–1 Eab = 50 kJ (2) Azeotropic mixture have same composition in vapour and liquid phase. Interactions between different components is different from pure components, hence boiling point can be lower or higher. (3) At cathode, reduction occurs according to following reaction. -1 - l° = L °m (HCl) + L °m (NaA) - L°m (NaCl) 100 = 150 – Eab -1 Na + A Lm(HA) = Exp.No. 66. Cl- H (3) As k¢ > k¢¢ , E ¢a < E a¢¢ (Greater the rate constant, lesser is the activation energy). (2) DH = Ea f - Eab +4 65. ° (NaCl) (3) Given: Lm = 126.4 S cm2 mol–1, L°m (HCl) = Rate = k [A] Þ k = t1/2 = 72. 0.693 2 ´10-3 2.0 ´ 10 -5 = 2 ´ 10 -3 [0.01] = 347 sec. (2) p = CRT w ´ R ´ T 68.4 ´ 0.0821 ´ 273 = = 4.48 atm mV 342 ´ 1 (2) The value of DrG depends on n value as per the equation DrG = –nFEcell p= 73. So, assertion statement is correct Ecell is an intensive property while DrG is an extensive thermodynamic property So, reason is correct but not explaining the assertion. 6 NEET PT - XII/01 74. (1) For one molal solution, 1 mol of solute should be present in 1000 g of solvent. Or we can say that 0.5 mol of solute should be present in 500g of solvent. 75. (4) k1 = A × e –Ea /RT 1 –E k 2 = A × e a 2 /RT On dividing equation (ii) by (i) k Þ 2 =e k1 æk ln ç 2 è k1 76. So, l°m(CH3COOH) = l°m(CH3COO–) + l°m(H+) So l°m(CH3COOH) .....(ii) = l°m(CH3COOK) + (E a – Ea ) 1 2 RT 10, 000 ö E a1 – E a 2 = =4 ÷= ´ 300 RT 8.314 ø (2) Cu2+ + 2e– ¾® Cu, DG1° = – 2F(0.34) ...(i) ...(ii) Cu+ + e– ¾® Cu, DG2° = – F(0.522) Subtract (ii) from (i) Cu2+ + e– ¾® Cu+, DG3° = –F(E0) ° ° ° \ DG1 – DG2 = DG3 Þ –FE° = –2F(0.34) + F(0.522) (3) Relative lowering in vapour pressure = l°m(AB) = l°m(A+) + l°m(B–) .....(i) Þ E° = 0.68 – 0.522 = 0.158 V 77. 82. (1) According to Kohlrausch’s law 83. Þ 0.222 = 0.7995 - Rate = k [ A]a [ B]b (K is constant) Taking ratio of (1) and (2) entry. Þ 160 nA 760 - p 160 = 1 Þ XA = = Þ nA + nH 2O 760 160 54 4 + 160 18 or 8 ´ 10 -2 79. 80. 81. 3 2 2 o o or 184 = ´ 200 + ´ pB or 184 = 120 + pB 5 5 5 or pºB = 160 torr. (1) Molarity depends on the volume of a solution which can be changed with change in temperature. [0.02]b [0.02]a = [0.04]a [0.04]b [2] = [2]a Þ a = 1 = 2 ´ 10 –2 = k [ A]1[ B ]1 k= 10 = antilog 1.2036 a-x (2) P = PA + PB = xA pAo + xB pBo where P = total pressure, p = partial pressure pº = vapour pressure, x = mole fraction [0.04]b [0.02]a 4 ´ 10 -2 [0.02]a [0.04]b Order w.r.t [A] 10 = 1.2036 a–x 10 = 0.625 g or a - x = 15.98 (4) Daniell cell is a type of galvanic cell. 2 ´ 10 -2 = Order w.r.t [ B] = b = 1 Taking ratio of (2) and (3) entry, 0.693 –1 2.303 10 hr = log 24 96 a–x 10 = 15.98 a-x 4 ´ 10 -2 ...(i) 2 = [2]b Þ [2]1 = [2]b 3 Þ p = ´ 760 = 570 torr.. 4 or log 0.0591 1 log 2 [Ag+ ]2 Þ [Ag+] = 10–9.8 Ksp (AgCl) = [Ag+][Cl–] = 10–9.8 × 1 84. (4) A + B ® P According to rate law expression \ 54 mL = 54 g water] k= 0.0591 [H + ]2 log n PH 2 ´ [Ag + ]2 Ecell = E°cell - ( p° - p) = XA p° (2) x y æx- yö - = z+ ç ÷ 2 2 è 2 ø (1) The given EMF at those conditions is equal to standard electrol potential. The cell reaction: H2(g) + 2Ag+ (aq) ® 2H+ (aq) + 2Ag(s); n = 2 =z+ [Given p° = 760 torr. Let, d water = 1 g/mL 78. 1 1 l° (H SO ) – l° (K SO ) 2 m 2 4 2 m 2 4 2 ´ 10-2 0.02 ´ 0.02 2 ´ 10 -2 ´ 104 100 = = 50 4 2 (2) Effective collision depends on proper orientation and colliding energy. The colliding energy has to overcome the energy of activation in order to form the product. (4) Correct matching for pair (iii) will be [G (conductance) – siemens or ohm–1(S).] (3) For the reaction A ® Product Given t1/ 2 = 1 hour For a zero order reaction = 85. 86. 87. \ t1 / 2 = [ A0 ] 2k NEET PT - XII/01 or k = [ A0 ] 2 t1/ 2 7 = 2 = 1 mol L–1 hr–1 2 ´1 K f ´ wH DTf = MH Further for a zero order reaction, 19.23 = dx change in concentration k= = dt time 88. 89. 90. 91. MH = %/atomic mass Molratio = mol C 92.3% 92.3/12 = 7.7 7.7/7.7 = 1 H 7.7% 7.7/7.7 = 7.7 7.7/7.7 = 1 \ Empirical formula = CH Empirical formula weight = 12 + 1 = 13 95. Thus, molecular formula = (CH)4 = C4H4 (2) 4A + 3B ® 6C + 9D Rate of reaction : - (2) Molarity is intrinsic property. Hence, it is independent of amount of solution. \ r = k[A]α [B]β ...(i) 2r = k[2A]α [B]β ...(ii) β 3r = k[A] [9B] Dividing eq. (ii) by eq. (i) 1 d [A ] 1 d [ B] 1 d [ C ] 1 d [ D ] == = 4 dt 3 dt 6 dt 9 dt Rate of reaction = Now, - 3 = 9β or, 3 = 32β or, 2β = 1 or, β = 1/2 1 3 = 2 2 92. (1) Effective collision is the deciding factor for complex reactions. 93. (4) Let, volume of solution = 1 L Mole of NaOH = 2 Mass of NaOH solution = volume × density = 1000 × 1.28 = 1280 g Mass of H2O = (1280 – 2 × 40) = 1200 g = 1.2 kg 1 d [B] = 1´10-2 3 dt d [B] = 3 ´10-2 dt Rate of consumption of B = 3 × 10–2 mol L–1 s–1 \ Consumption of B in 10s = 3 × 10–2 × 10 = 3 × 10–1 = 0.3 mol L–1 = 30 × 10–2 mol L–1 ...(iii) 2 = 2α or α = 1 Dividing eq. (iii) by eq. (i) 96. or - (4) é MnO 4- + 8H + + 5e- ® Mn 2+ + 4H 2O ù ´ 2 ë û E° MnO-4 /Mn 2 + \ Order of the reaction = 1 + Molality (m) = 94. 1 d [C] 1 = ´ 6 ´10-2 6 dt 6 = 1 × 10–2 mol L–1 s–1 A + B ¾¾ ®C + D α % Molecular weight 52 Factor (n) = Empirical formula weight = 13 = 4 C (3) 40 ´ 0.02 ´ 1000 Mc ´ 0.8 40 ´ 0.02 ´ 1000 = 52g 19.23 ´ 0.8 Element strong electrolyte (KI) weak electrolyte (H2CO3) ] 1000 Wc Molar mass of solute 0.50 - 0.25 1= Þ time = 0.25 hr.. time (1) For 10K rise in temperature, the rate of reaction nearly doubles. (2) Statement I: KI is strong electrolyte, it dissociates completely. So, lm increases slowly on dilution. Statement II: In weak electrolyte lm increases, sharply as the dissociation increases. lm ´ Mole of NaOH 2 = = 1.67 m Mass of solvent (kg) 1.2 (3) Melting point of camphor = 176°C Melting temperature of camphor solution = 156.7°C Thus, DTf for camphor solution = 176 – 156.77 = 19.23°C \ Depression in freezing point 97. = +1.510V 1 é ° + -ù ê H 2 O ® 2 O 2 + 2H + 2e ú ´ 5 E H2 O/O2 = -1.223V ë û + 2+ 5 2MnO 4 + 6H ® 2Mn + O2 + 3H 2 O 2 E °cell = +1.510V - 1.223V = 0.287 V (1) A ® Products Given: Initial conc. [A0] = 0.1 M Conc. After 5 min [At] = 0.001 M t = 5 min. For first order reaction k= [A ] 2.303 2.303 æ 0.1 ö log 0 = log ç ÷ t [A t ] 5 è 0.001 ø k = 0.9212 min–1 8 98. 99. NEET PT - XII/01 (1) r = K[A]1[B]1 0.1 = K(20)1 (0.5)1 0.40 = K(x)1 (0.5)1 0.80 = K(40)1 (y)1 From (i) and (ii) x = 80 From (i) and (iii) y= 2 (2) Arrhenius equation ... (i) ... (ii) ... (iii) 112. 113. 114. k = Ae- Ea / RT 115. ln k = ln A + ln e - Ea / RT 116. E ln k = ln A - a R æ1ö ç ÷ èT ø Slope of ln k vs Ea 1 curve, m = T R ...... (1) Ea R 3 Ea = 5× 10 × 8.314 J/mol = 41.57 × 103 J/mol = 41.5 kJ/mol 100. (1) A-III, B-I, C-II, D-IV -5 ´103 = - PART - III : BOTANY 101. (3) The correct sequence of formation of female gametophyte of flowering plants is- Meiosis in megaspore mother cell and formation of megaspore tetrad ® Functional megaspore undergoes three mitotic divisions, results in the formation of eight nuclei ® Cell walls are laid down ® Formation of seven cells with eight nuclei. 102. (4) The endosperm is absent in the seed of pea because endosperm is completely consumed by the developing embryo. 103. (2) Xenogamy refers to the transfer to pollen grains from anthers of one plant to stigma of a different plant which during pollination brigs genetically different types of pollen grains to stigma. 104. (1) 105. (4) In majority of aquatic plants, the flowers emerge above the level of water. These may be pollinated by insects or wind eg.: Water hyacinth and water lily. 106. (3) Sporopollenin is the most resistant known biological material. It is resistant to several biological and chemical decomposition and can be preserved as fossils. 107. (4) 108. (3) The fruits that develop without fertilization are known as parthenocarpic fruits such as banana. 109. (2) Polyembryony ® Orange Parthenocarpy ® Banana False fruit ® Apple Embryo Sac ® Female gametophyte 110. (3) Assertion is incorrect and reason is correct. Pollination by wind is more common among abiotic pollinations. 111. (2) The correct stages of development of a dicot embryo in the order of their occurrence are – (iii). Formation of zygote ® (iv). Formation of globular embryo ® (i). 117. 118. 119. 120. 121. 122. 123. 124. Formation of heart shaped embryo ® (ii). Formation of typical dicot embryo. (2) (2) Syngamy is the most vital event of sexual reproduction is perhaps the fusion of gametes, resulting the formation of a diploid zygote. (3) • Wheat ® Albuminous seed • Black pepper ® Perisperm • Cashew ® False fruits • Citrus ® Polyembryony (2) In a fertilized ovule n, 2n and 3n conditions occur respectively in egg, nucellus and endosperm. (4) Cleistogamy is a self-fertilization that occurs within a permanently closed flower. In cleistogamous flower, the anther and stigma lies close to each other. When anther dehisces in the flower buds, pollen grains come in contact with the stigma to effect pollination. Thus, cleistogamous flowers are invariably autogamous as there is no chance of cross - pollen landing on the stigma. Cleistogamous flowers produce assured seed set even in the absence of pollinators. (1) Synergids bear prominent structure called ‘filiform’ apparatus which are finger like projections. This apparatus is present in upper part of each synergid. This apparatus is useful for the absorption and transportation of materials from the nucellus to the embryo sac. (4) Statement (iv) is not the characteristic of wind pollinated flowers. Wind pollination requires such type of the pollen grains that are light and non-sticky so that they can be transported in wind currents. They often possess wellexposed stamens so that the pollens are easily dispersed into wind currents, and large often-feathery stigma to easily trap air-borne pollen grains. Wind pollinated flowers often have a single ovule in each ovary and numerous flowers packed into an inflorescence. (3) Non-albuminous seed ® Residual endosperm absent Albuminous seed ® Residual endosperm present Perisperm ® Residual nucellus Pericarp ® Fruit wall (1) The gynoecium represents the female reproductive part of the flower that consists of pistil. Each pistil comprises three parts, i.e., stigma, style and ovary. (1) Majority of insect pollinated flowers are large-sized. These flowers are colorful and possess fragrance to attract the insects. (1) Tapetum is important for the nutrition an d development of pollen grains, as well as a source of precursors for the pollen coat. (4) A – III; B – IV; C – I; D – II (3) All the statements are correct about self incompatibility. Self-incompatibility is a general name for several genetic mechanisms in angiosperms, which prevent self-fertilization and thus encourage outcrossing and allogamy. In plants with self - incompatibility, when a pollen grain produced in a plant reaches a stigma of the same plant or another plant with a similar genotype, the process of pollen germination, pollen tube growth, ovule fertilization, and embryo development is halted at one of its stages, and consequently no seeds are produced. NEET PT - XII/01 125. (2) In general the egg apparatus of embryo sac in angiosperm consists of one egg cell, two synergids, three antipodal cells, two polar nuclei. 126. (2) In over 60% of angiosperm pollen grain is liberated at 2 celled stage. 127. (1) Megaspore mother cell (MMC) undergoes meiosis to form four haploid cells (called megaspores) and the process of formation is known as megasporogenesis. The MMC undergoes meiotic division results in the production of four megaspores. 100 functional megaspores are produced by 100 MMC, since three out of four megaspores degenerate in each case. 128. (4) 129. (3) 130. (4) The attachment point of funicle and body of ovule is known as hilum. 131. (4) Two types of pollination are recognised based on the destination of pollen grains. When pollen grains are transferred from an anther to the stigma of the same flower, the process is called self pollination or autogamy. Cross pollination is further classified depending on whether the pollination has occurred between two flowers on the same plant (geitonogamy) or between two flowers on different plants (xenogamy). 132. (3) Pollen grains are rich in nutrients therefore used as food supplements. Athletes and race horses use these tablets to enhance performance. 133. (2) Endosperm of angiosperms is triploid in nature. As, one of the male gamete moves towards the egg cell and fuses with its nucleus results in the formation of a diploid zygote where as the other male gamete moves towards the two polar nuclei located in the central cell and fuses with the polar nuclei results in the formation of a triploid primary endosperm nucleus. 134. (1) 135. (2) As the anther develops, the microspore mother cells of the sporogenous tissue undergoes meiotic divisions to form microspore tetrads. After dehydration, the microspore tetrad is separated into pollen grains. 136. (3) 137. (3) A – III; B – I; C – IV; D – II 138. (3) 139. (4) Double fertilisation is a characteristic feature of flowering plants. It involves two fusions in which one male gamete fuses with egg cell to form zygote and other male gamete fuses with the diploid secondary nucleus to produce triploid primary endosperm nucleus. 140. (2) A – IV; B – III; C – II; D – I 141. (4) 142. (3) The pollen grains represent the male gametophytes. As, the anthers mature and dehydrate, the microspores dissociate from each other and develop into pollen grains. So, embryo sac is to ovule as pollen grains is to an anther. 143. (3) Egg apparatus consists of two synergids and one egg cell lying at the micropylar end. Synergids bear prominent structure called ‘ filiform’ apparatus which are finger like projections. Synergids guide the path of pollen tube towards the egg, help in obtaining nourishment from the outer nucellar cells and also function as shock absorbers during the penetration of pollen tube into the embryo sac. Cytoplasm of egg is inactive, rich in ribosomes, and contains plastids. 144. (2) Aquatic plants such as water hyacinth & Lily, the flower semerge above the level of water & are pollinated by insects & wind. 9 145. (1) The majority of angiosperms bear chasmogamous flowers, which means the flowers expose their mature anthers and stigma to the pollinating agents. There is another group of plants which set seeds without exposing their sex organs. Such flowers are called cleistogamous and the phenomenon is cleistogamy. 146. (3) 147. (3) Primary endosperm nucleus is formed by the fusion of diploid secondary nucleus with a male gamete. Therefore, it is triploid. Zygote is formed by fusion of two gametes and thus it is diploid. Synergids are the cells of gametophyte and hence these are haploid. 148. (1) One can study pollen germination in plants like pea in a lab by using 10% of sugar solution. 149. (1) 150. (4) Cleistogamy is the phenomenon, where flowers never open and in such flowers, only self-pollination occurs within the bud (unopened flower). Bisexual flowers which do not open at all are called cleistogamous. In such flowers, anthers and stigma lie close to each other. When the anthers dehisce in the flower buds, pollen grains come in contact with the stigma and pollination occurs. So, there is no chance of crosspollination in this type of flower. Therefore, both statements are true. PART - IV : ZOOLOGY 151. (4) Both Statement I and Statement II are correct. 152. (2) The glandular tissue of each breast is divided into 15-20 mammary lobes containing clusters of cells called alveoli. 153. (4) A - II, B - IV, C - III, D - I 154. (1) 155. (1) 156. (1) Both assertion and reason are correct but reason is not the correct explanation of assertion. 157. (4) The male sex accessory ducts include rete testis, vasa efferentia, epididymis and vas deferens. 158. (4) 159. (1) Diaphragms- they cover the cervix blocking the entry of sperms Contraceptive pills – inhibit ovulation and implantation Intra uterine devices – increases phagocytosis of sperm within uterus Lactational amenorrhea – absences of menstrual cycle and ovulation following parturition. 160. (4) Seminal plasma is secreted from male acessory glands and it is rich in fructose, calcium and certain enzymes. 161. (4) 162. (3) The correct option is (3) because placenta secretes human chorionic gonadotropin (hCG). Zona pellucida is a primary egg membrane secreted by the secondary oocyte. The secretions of bulbourethral glands help in lubrication of the penis Leydig cells synthesise and secrete testicular hormones called androgens. 163. (2) The spermatids are transformed into spermatozoa (sperms) by the process called spermiogenesis. After spermiogenesis, sperm heads become embedded in the Sertoli cells, and are finally released from the seminiferous tubules by the process called spermiation. 164. (3) Both LH and FSH attain a peak level in the middle of menstrual cycle (about 14th day) resulting in ovulation. 165. (4) Milk produced during the initial few days of lactation is called colostrum. This contains several antibodies absolutely essential to develop resistance for the new-born babies. 10 166. (1) In this method, ova from female and sperms from male are collected and are induced to form zygote under simulated condition in the lab. 167. (4) According to the World Health Organisation (WHO), reproductive health means a total well-being in all aspects of reproduction, i.e., physical, emotional, behavioural and social. 168. (3) LNG 20 is hormone releasing IUD that releases levonorgestrel. It is responsible to increase the sperm phagoeytosis. Multiload 375, Cu T and Cu 7 are copper releasing IUDs. 169. (1) 170. (3) The acrosome (head of the sperm) contains the necessary enzymes (hyal uronidase and acrosin) to penetrate the membrane of the ovum. 171. (4) Gonorrhoea, Syphilis, Genital herpes are sexually transmitted diseases. 172. (2) Gonorrhoea is a bacterial disease which can be treated with the help of antibiotics and cured completely. Rest other diseases are not completely cured as other mentioned options are viral diseases. 173. (4) 174. (2) By the end of the 12 weeks, most of the major organ systems are formed. 175. (3) The head of the sperm is known as acrosome that has enzymes which help sperm to enter an egg. 176. (2) Graafian follicle releases secondary oocyte from the ovary by the process of ovulation.The fluid filled cavity of tertiary follicle is known as antrum. 177. (2) Rapid declines in death rate, maternal mortality rate (MMR) and infant mortality rate (IMR) as well as an increase in number of people in reproducible age are probable reasons for the present increase in india’s population. 178. (4) 179. (1) Sexually transmitted diseases (STDs) are infections that are commonly spread by sex, especially vaginal intercourse, anal sex or oral sex. The causes of STDs are bacteria, parasites, yeast, and viruses. 180. (2) Semen, or seminal fluid, is an alkaline fluid that contains spermatozoa embedded in seminal plasma. Semen is ejaculated by male reproductive system during orgasm. 181. (1) Both the statements are correct. Vas deferens receives a duct from seminal vesicle and opens into urethra as the ejaculatory duct. The cavity of the cervix is called cervical canal which along with vagina forms birth canal. 182. (1) To get rid of unwanted pregnancies and to prevent the fatality or harmfulness to the mother or to foetus or both due to the continuation of pregnancy are the reasons on the basis of which pregnancy can be terminated. 183. (1) Blastomeres are a type of cell produced by cleavage (cell division) of the zygote after fertilization and are an essential part of blastula formation. 184. (4) A - III, B - IV, C - I, D - II 185. (3) The use of condoms during coitus is some of the simple precautions to avoid contacting STIs like AIDS and syphilis. 186. (2) The correct matching is: Vasectomy is a surgical method of contraception Coitus interruptus is a natural method of contraception Cervical cap is a barrier method of contraception Saheli is an oral method of contraception which is a nonsteroidal pill NEET PT - XII/01 187. (2) Lactational amenorrhoea do not play any role in phagocytosis of sperms. 188. (4) 189. (2) 190. (2) 191. (3) Oocytes start division and enter into prophase-I of the meiotic division and get temporarily arrested at that stage, called primary oocytes. Oogenesis is initiated during the embryonic development stage when a couple of million gamete mother cells (oogonia) are formed within each fetal ovary; no more oogonia are formed and added after birth. 192. (4) Contraceptive pills have to be taken daily for a period of 21 days starting preferably within the first five days of menstrual cycle. It helps in the prevention of conception. As long as the mother feeds breast the child fully, chances of conception are almost nil only up to a maximum period of six months following parturition. 193. (4) Condoms are used as barriers made of thin rubber/ latex sheath used to cover the penis in the male or vagina and cervix in females. It prevents the deposition of ejaculated semen into the vagina of the female. It should be discarded after a single use. It is also a safe guard against transmission of AIDS and other Sexually Transmitted Diseases (STDs). 194. (3) 195. (4) Such type of infections or disease that are spreaded through sexual intercourse are known as veneral diseases or sexually transmitted disease. These disease are transmitted by the sharing of infected needles, transfusion of blood from an infected person or from an infected mother to foetus. 196. (1) In lactational amenorrhea, pills and emergency contraceptives methods, there is the involvement of hormones. Lactational amenorrhea (absence of menstruation) is based on the fact that ovulation and therefore the cycle do not occur during the period of intense lactation following parturition. Prolactin is the major hormone responsible for milk production and is present in sufficient quantities in almost all women to allow the establishment of normal lactation. Emergency contraception methods include emergency contraception pills (ECP), intrauterine device, e.g., LNG20 (Levonor- gestrel) and ulipristal acetate. CuT and barrier method do not involve any hormonal role. 197. (4) Both Statement I and Statement II are correct. 198. (2) Fully developed foetus and the placenta induce foetal ejection reflex. Foetal ejection reflex is also called mild uterine contraction. 199. (2) Such type of infections or disease that are spreaded through sexual intercourse are known as reproductive tract infections (RTI) or sexually transmitted disease. These disease are transmitted by the sharing of infected needles, transfusion of blood from an infected person or from an infected mother to foetus. 200. (4) Uterus is also known as womb. Oogenesis is the process of formation of mature female gametes. Primary oocytes get surrounded by layer of granulosa cells.