SR MPC JEE MAINS GT 6 EX DT 12-07-2020.pdf - Meluha ...

Page | 1 MPC TOTAL GT – 10 :: JEE MAINS MODEL :: 00-00-0000

MELUHA INTERNATIONAL SCHOOL HYDERABAD

SR MPC Date: 12-07-2020 Time: 3 Hours Max. Marks: 300

JEE MAIN MODEL MATHEMATICS

Section Question type +Ve

Marks - Ve

Marks No.of

Qs Total marks

Sec – I(Q.N : 01 – 20) Questions with Single Answer Type 4 -1 20 80

Sec – II(Q.N : 21 – 25) Questions with Numerical Answer Type (+/ - Decimal Numbers)

4

0

5

20

Total

25

100

PHYSICS


Marks - Ve

Marks No.of

Qs Total marks



4

0

5

20

Total

25

100

CHEMISTRY


Marks - Ve

Marks No.of

Qs Total marks



4

0

5

20

Total

25

100

JEE MAINS GT-6


SECTION – I (SINGLE CORRECT ANSWER TYPE)

This section contains 20 multiple choice questions. Each question has 4 options (A), (B), (C) and (D) for its answer, out of which ONLY ONE option can be correct. Marking scheme: +4 for correct answer, 0 if not attempted and -1 if not correct.

MATHEMATICS

1. If 2 1g x x x and 24 10 5gof x x x then 54

f

is equal to

A) 32

B) 12 C) 3

2 D) 1

2

2. The logical statement ~p q q p is equivalent to

A) p B) q C) ~p D) ~q

3. If 2

01 n n

nx Tan

and 2

0

n

ny Cos

, for 04 , then:

A) 1 1y x B) 1 1x y C) 1 1y x D) 1 1x y

4. The coefficient of 4x in the expansion of 1021 x x A) 620 B) 625 C) 618 D) 615 5. The number of all 3 3 matrices A, with entries from the set 1,0,1 such that the sum of the

principal diagonal elements of 'AA is 3 are A) 673 B) 677 C) 672 D) 675 6. Let ,a b and c be three vectors such that 3a , 5b , . 10b c and the angle between b

and c is 3 . If a is perpendicular to the vector b c then. a b c is

A) 32 B) 30 C) 35 D) 38

7. Six symmetrical dice are thrown simultaneously the probability of having different points on

them is

A) 16

B) 136

C) 66

66P D) 1

8

8. The variance of first 20 natural numbers is

A) 1334

B) 37912

C) 1332

D) 3994

9. The locus of the point z x iy satisfying 2 12

z iz i

is

A) x-axis B) y-axis C) y=2 D) x=23

10. The system of linear equations 2 2 5x y z , 2 3 5 8x y z , 4 6 10x y z has

A) Infinitetly many solutions when 2 B) a unique solutions when 8 C) no solution when 8 D) no solution when 2

11. If 18 6 5f x f xx

and 2y x f x then dydx

at 1x is equal to

A) 112

B) 114

C) 1914

D) 114


12. If orthocentre and circumcentre of triangle are respectively 1,1 and 3,2 , then the co-ordinates of its centroid are

A) 7 5,3 3

B) 5 7,3 3

C) 7,5 D) 0,0

13. 2

3 4 2

12 2 1

x dxx x x

is equal to

A) 4 2

2

2 2 1x x Cx

B) 4 2

3

2 2 1x x Cx

C) 4 2

2

2 2 12

x x Cx

D) 4 22 2 1x x C

x

14. If 1

4 5f x

x x

and 2

1g xx

then number of points of discontinuity of f g x are

A) 3 B) 4 C) 7 D) 2

15. If the lines 1 2 3x y z , 1 2 3

3 1 4x y z

and 1 23 2

x k y zh

are concurrent, then

A) 2, 6h k B) 1 , 22

h k C) 6, 2h k D) 12,2

h k

16. The point on the parabola 22y x , which is nearest to the point 0,3 is

A) 4,8 B) 93,2

C) 2,2 D) 11,2

17. In the mean value theorem 'f b f a b a f c , a c b . If 4a , 9b and

f x x , then the value of C is A) 8 B) 5.25 C) 4 D) 6.25

18. If 2ln 1

xe Sinxx

Cosx x

, then the value of

0limx

xx

is

A) 0 B) 2 C) -1 D) -2 19. The area bounded by the curve 22y x x and the line y x is

A) 72

B) 92

C) 29

D) 273

20. 22 xdy y edx

, then y is

A) 223

x xCe e B) 2213

x xx e e C C) 22

3x xCe e c D) 22

3x xe e c

SECTION- II

(Numerical Value Answer Type) This section contains 5 questions. The answer to each question is a Numerical values comprising of positive or negative decimal numbers. Marking scheme: +4 for correct answer, 0 in all other cases.

21. Let ; 1 50x n N n . If

;A n x n is a multiple of 2 } and

;B n x n is a multiple of 7} , then the number of elements in the smallest subset of x containing both A and B is_______


22. The sum 7

1

1 2 14n

n n n

is equal to _______

23. The number of 4 letter words (with or without meaning) than can be formed from the eleven letters of the word EXAMINATION is ________

24. If 11 16 log2 5Cosx Sinx dx x Cosx Sinx CCosx Sinx

, then _____

25. The chord joining the points 5,5 and 11,227 on the curve 23 11 15y x x is parallel to tangent at a point on the curve. Then the abscissa of the point is ________

SECTION – I

(SINGLE CORRECT ANSWER TYPE) This section contains 20 multiple choice questions. Each question has 4 options (A), (B), (C) and (D) for its answer, out of which ONLY ONE option can be correct. Marking scheme: +4 for correct answer, 0 if not attempted and -1 if not correct.

PHYSICS

26. Apparent frequency is 200Hz when listener is moving at 40 m/s towards a stationary source. Apparent frequency is 160 Hz when he moves away from the stationary source with the same speed. Velocity of sound is

A) 300ms-1 B) 330ms-1 C) 360ms-1 D) 310ms-1 27. A light ray travels in two media A and B with speeds 2×108m/s and 2.4×108m/s. The critical

angle between them is

A) 1 8sin9

B) 1 5sin6

C) 1 5n6

a

t D) 1 8cos9

28. In a young’s double slit experiment with wavelength 5890A0, there are 60 fringes in the field of vision. How many fringes will be observed in the same field of vision if wavelength used is 5460A0?

A) 65 B) 60 C) 55 D) 50 29. An ellipsoidal cavity is carved with in a perfect conductor. A positive charge q is placed at the

centre of the cavity. The points A and B are on the cavity surface as show in the figure then a) Electric field near A in the cavity = Electric field near B in the cavity b) Charge density at A = charge density at B c) Potential at A= Potential at B d) Total electric flux through the surface of the cavity is 0/q

B

A

q

A) a,b,c,d are correct B) a,b,c are correct C) Only a and b are correct D) Only c and d are correct 30. The torque required to keep a magnet of length 20cm at 300 to a uniform field is 2×10-5 N-m.

The magnetic force on each pole is A) 2×10-3 N B) 2×10-4 N C) 2×10-6 N D) 4×10-4 N 31. In a induction coil, the coefficient of mutual inductance is 4H. If a current of 5 A in the

primary circuit is cut off in 1/500s, the emf induced in the secondary circuit will be A) 30KV B) 20KV C) 10KV D) 5KV 32. If the charge on the body is increased by an amount of 2C. the energy stored in it is increases

by 21%. The original charge on the body is A) 2C B) 10C C) 15C D) 20C


33. In rutherford α particle scattering experiment with their gold foil is 8100 scintillations per minute are observed at an angle of 600. The number of scintillations per minute at 1200 will be

A) 200 B) 500 C) 900 D) 1600 34. For a transistor, the current gain of a common base configuration is 0.8. if the transistor in

common emitter configuration and the base current changes by 5mA. Then the change in collector current is

A) 1mA B) 4mA C) 10mA D) 20mA

35. The KE of the photoelectrons is E when the incident wavelength is 2 . The KE becomes 2E

when the incident wavelength is λ .3

The work function of the metal is

A) hc

B) 2hc

C) 3hc

D) 3hc

36. A radioactive nucleus of mass M emits a photon of frequency and the nucleus recoils. The recoil energy will be

A) Mc2- h B) h2 2/2Mc2 C) Zero D) h 37. A charged particle is accelerated through a potential difference of 12KV and acquired a speed

of 106 m/s. It is then injected perpendicularly in to a magnetic field of strength 0.6T the radius of the circle is

A) 2cm B) 4cm C) 6cm D) 8cm 38. 5grams of steam at 1000 C is passed in to calorimeter containing liquid. Temperature of liquid

raises from 320C to 400C. then water equivalent of calorimeter and contents is A) 40gram B) 160gram C) 375gram D) 425gram

39. At pressure of 24×105 dyne/Cm2. The volume of O2 is 10 liter and mass is 20 gram the r.m.s. velocity will be

A) 800m/s B) 400m/s C) 600m/s D) 200m/s 40. A meter bridge is set up as shown to determine an unknown resistance X using a standard

resistance 10Ω. The galvanometer shows null point when tapping jockey is at 52cm mark. The end corrections are 1cm as 2cm respectively for the ends A and B. The determine value of X is

10X

G

A B A) 10.6Ω B) 10.8Ω C) 10.10Ω D) 11.2Ω 41. The rms voltage VL, VC and VR are across inductor L, capacitor C and resistance R in LCR

series circuit. Their ratio is 1:2:3. If the rms voltage of AC source is 100V, then VR is nearly equal to

A) 40V B) 60V C) 90V D) 100V 42. The resultant of two equal forces is 141.4N when they are mutually perpendicular. When they

are inclined at an angle 1200 then the resultant force will be in N is _____ A) 100 B) 200 C) 300 D) 400 43. If the particle is moving along a straight line given by the relation 32 3 4x t t where x is in

cm and t in sec. Its average velocity during the third second in cm/s is A) 63 B) 73 C) 84 D) 90 44. A horizontal jet of water coming up out of a pipe of area of cross section 20cm2 hits a vertical

wall with a velocity of 10 m/s and rebounds with the same speed the force exerted by the water on the wall in N is____ A) 200 B) 300 C) 400 D) 500

45. The youngs modules of the material of the rod is 20×1010 Pascal. When the longitudinal strain is 0.04%. The energy stored per unit volume is

A) 16×103J/m3 B) 20×103J/m3 C) 30×103J/m3 D) 40×103J/m3


SECTION-II (Numerical Value Answer Type)

This section contains 5 questions. The answer to each question is a Numerical values comprising of positive or negative decimal numbers. Each question has 4 options (A), (B), (C) and (D) for its answer, out of which ONLY ONE option can be correct. Marking scheme: +4 for correct answer, 0 in all other cases.

46. A ring and disc of same mass roll with out slipping along a horizontal surface with same

velocity if the K.E of ring is 8J then that of the disc in joule is ___ 47. Three masses 0.1kg, 0.3kg , 0.4kg are suspended at the end of the spring when the 0.4kg is

removed the system oscillate with a period of 2S. when 0.3kg mass is also removed the system will oscillates with period in sec is____

48. A satellite is launched in to a circular orbit of radius R around the earth while the second satellite is launched in to an orbit of radius 1.02R the percentage change in time periods of the two satellite is ____

49. A body of mass 6kg under a force which causes displacement in it which is given by 2tS = m4

where t is time the work done in joule by the force in 2sec is____ 50. The work done in forming a soap films of size 10 cm×10cm will be if the surface tension if

soap solution is 3×10-2N/m is ____×10-4J

SECTION – I (SINGLE CORRECT ANSWER TYPE)

This section contains 20 multiple choice questions. Each question has 4 options (A), (B), (C) and (D) for its answer, out of which ONLY ONE option can be correct. Marking scheme: +4 for correct answer, 0 if not attempted and -1 if not correct.

CHEMISTRY

51. Consider a titration of potassium dichromate solution with acidified Mohr’s salt solution using diphenylamine as indicator. The number of moles of Mohr’s salt required per mole of dichromate is

A) 3 B) 4 C) 5 D) 6 52. P is the probability of finding the 1s electron of hydrogen atom in a spherical shell of

infinitesimal thickness, dr, at a distance r from the nucleus. The volume of this shell is 24πr dr . The qualitative sketch of the dependence of P on r is

A) B) C) D) 53. Among the following species, indentify the isostrucural paris. - +

3 3 3 3 3NF ,NO ,BF , H O , HN A) 3 3 3 3, ,NF NO and BF H O B) 3 3 3 3, ,NF HN and NO BF

C) 3 3 3 3,NF H O and NO BF D) 3 3 3 3, ,NF H O and HN BF

54. In van der waals equation of state for a non-ideal gas, the term that accounts for intermolecular forces is

A) (V- b) B) RT C) 2

aPV

D) 1RT


55. For the reversible reaction, 2 2 3N g + 3H g 2NH g at 5000C, the value of Kp is 1.44×10-5 when partial pressure is messured in atmosperers. The corresponding value of KC, with concentration in mole litre-1, is

A)

5

21.44 10

0.082 500

B)

5

21.44 10

8.314 773

C)

5

21.44 10

0.082 773

D)

5

21.44 10

0.082 773

56. The following compounds have been arranged in order of their increasing thermal stabilities. K2CO3(I), MgCO3(II), CaCO3(III), BeCO3(IV) Identify the correct order A) I<II<III<IV B) IV<II<III<I C) IV<II<I<III D) II<IV<III<I 57. Most stable carbonium ion is : A) 2 6 4 2p NO C H CH B) 6 5 2C H CH C) 6 4 2p Cl C H CH D) 3 6 4 2p CH O C H CH 58. Cyclohexene on ozonolysis followed by reaction with zinc dust and water gives compound E.

Compound E on further treatment with aqueous KOH yields compound F. Compound F is

A) CHO

B) CHO

C) COOH

D)

2CO H

2CO H

59. Among the following, the surfactant that will form micelles in aqueous solution at the lowest molar concentration at ambient condition is :-

A) 3 2 315 3CH CH N CH Br B) 3 2 311

CH CH OSO Na

C) 3 2 6CH CH COO Na D) 3 2 311 3

CH CH N CH Br 60. The emf of the cell 2+ 2+Zn Zn 0.01M Fe 0.001M Fe at 298K is 0.2905 then the value of equilibrium constant

for the cell reaction is

A) 0.32

0.0295e B) 0.32

0.029510 C) 0.26

0.029510 D) 0.32

0.059110

61. The chemical composition of ‘slag’ formed during the smelting process in the extraction of copper is

A) 2Cu O FeS B) 3FeSiO C) 2CuFeS D) 2Cu S FeO 62. Which of the following represents the correct order of increasing first ionization enthalpy for

Ca, Ba, S, Se and Ar ? A) Ca <S<Ba<Se<Ar B) S<Se<Ca<Ba<Ar C) Ba<Ca<Se<S<Ar D) Ca<Ba<S<Se<Ar 63. The reaction of white phosphorus with aqueous NaOH gives phosphine along with another

phosphorus containing compound. The reaction type; the oxidation states of phosphourus in phosphine and the other product are respectively

A) redox reaction; -3and -5 B) redox reaction;3 and +5 C) disproportionation reaction; -3and +5 D) disproportionation reaction; -3 and +3 64. Among the following, the coloured compound is A) CuCl B) K3[Cu (CN)4] C) CuF2 D) [Cu(CH3CN)4]BF4 65. The reagent (s) for the following conversion,

Br Br ? H H

is / are A) AlcoholicKOH B) Alcoholic KOH followed by NaNH2

C) aqueous KOH followed by NaNH2 D) Zn/CH3OH

66. In the reaction HBr3OCH The products are

A) 3 2OCH and H B) 3Br and CH Br C) 3Br and CH O H D) 3OH and CH Br


67. The major product of the following reaction is

O

2R C H O HH an h y d rou s

A) a hemiacetal B) an acetal C) an ether D) an ester

68. MeO CHO + X

3+

3

CH COONaH O

CH = CHCOOH

The compound (X) is A) CH3COOH B) BrCH2-COOH C) (CH3CO)2O D) CHO-COOH 69. In the compound given below the correct order of the acidity of the positions X, Y and Z is

3Y

H N

XC O O H

+

3Z

N H

A) Z > X > Y B) X > Y > Z C) X > Z >Y D) Y > X > Z

70. The smog is essentially caused by the presence of A) Oxides of sulphur and nitrogen B) O2 and N2 C) O2 and O3 D) O3 and N2

SECTION-II (Numerical Value Answer Type)

This section contains 5 questions. The answer to each question is a Numerical values comprising of positive or negative decimal numbers. Each question has 4 options (A), (B), (C) and (D) for its answer, out of which ONLY ONE option can be correct. Marking scheme: +4 for correct answer, 0 in all other cases.

71. 0.2molal acid HX is 20% ionised in solution. Kf=1.86K molality-1. The freezing point of the

solution is ______ 72. The enthalphy change involved in the isothermal reversible expansion of 2 mole of an ideal

gas from a volume of 10 dm3 to a volume of 100 dm3 at 270C is______ 73. Consider a reaction aG+bH → Products. When concentration of both the reactants G

and H is doubled, the rate increases by eight times. However, when concentration of G is doubled keeping the concentration of H fixed, the rate is doubled. The overall order of the reaction is______

74. Total number of geometrical isomers for the complex [RhCOCl(PPh3)(NH3)] is______ 75. The total number of basic groups in the following form of lysine is______

3 2 2 2 2H N- CH - CH - CH - CH

CH - C

2H N O

O

*****


MELUHA INTERNATIONAL SCHOOL HYDERABAD

SR MPC Date: 12-07-2020 Time: 3 Hours Max. Marks: 300

KEY SHEET

MATHEMATICS

1) B 2) C 3) C 4) D 5) C 6) B 7) C 8) A 9) A 10) D

11) D 12) A 13) C 14) C 15) D 16) C 17) D 18) C 19) B 20) A

21) 29 22) 504 23) 2454 24) 10 25) 8

PHYSICS

26) C 27) B 28) A 29) D 30) B 31) C 32) D 33) C 34) D 35) A

36) B 37) B 38) C 39) C 40) A 41) C 42) A 43) B 44) C 45) A

46) 6 47) 1 48) 3 49) 3 50) 6

CHEMISTRY

51) D 52) D 53) C 54) C 55) B 56) B 57) D 58) A 59) B 60) C

61) B 62) C 63) C 64) C 65) B 66) D 67) B 68) C 69) B 70) A

71) –0.45 72) 38.03 73) 3 74) 3 75) 2

JEE MAINS GT–6


HINTS & SOLUTIONS MATHS

1. 2 1g x x x

24 10 5g f x x x

22 2 2 2 1x x

2 2f x x

5 5 12 24 4 2

f

2. ~P q q P

~ (~ ~ )P q q p ~ ( ~ )P q p ~ ~P C P 3. 2 2 4

01 . 1n n

nx Tan Tan Tan

2x Cos

2 2 4

01n

ny Cos y Cos Cos

2

1 1 1 11

y y y xSin x

4.

0 1 2

3 4

10 22 10 10 10 2

3 410 3 10 4

1 1 1

1 1

C C C

C C

x x x x x x

x x x x

Coefficient of 2 3 4

34 10 10 101 615C C Cx C

5. Trace 2 2 2 2 2 2 2 2 2

11 12 13 21 22 23 31 32 33 3TAA a a a a a a a a a

--(1) 1,0,1ija

(1) Happen for 6 zeros and (1,1,1) 1

6 zeros and (1,1,-1) 3

6 zeroes and (1,-1,-1) 3

6 zeroes and (-1,-1,-1) 1

Total possible ways = 9

6 1 3 3 1 672C

6. . 10 5 103

b c c Cos

a b c a b c

33.5.4. 3.5.4. 30

3 2Sin

=4

7. required probability 66

66P

8. 2 2 2 2 21 11 2 20 1 220 20

n

220 21 2 20 11 1 20 120 6 20 2

7 41 4412 4

1334

9. Z ai Z ai represents x-axis

10. 3 2

2 3 5 8 24 6

D

For 2 Hence no solution for 2

11. 18 6 5f x f xx

------(1)

Replace x by 1x

1 18 6 5f f xx x

From (1) and (2) 1 68 1028

f x xx

2 3 21 8 6 1028

y x f x x x x

21 24 6 2028

dy x xdx

1

1 124 6 2028 14x

dydx

12.

G divides H5 in the ratios 2:1 internally 7 / 3,5 / 3G

13. 3 5

2 4

1 1

2 12

x xI dx

x x

14

dtIt

12

t c

Put 2 4

2 12 tx x

3 5

4 4 dx dtx x

4 2

2 4 2

1 2 1 2 2 122 2

x xC cx x x


14.

4

2 2

2 2

11 1 4 1 5 14 5

xf g xx x

x x

f x is not defined at 4, 5

g x is not defined at 0

f g x is not defined at 1 1,2 5

No of discontinouity points=5 15. Co-ordinates of a general point on first line

can be taken as , 2 ,3 The general point on second line is

3 1, 2,4 3 If the lines intersect, then they have a

common point so, for some value of and must have

3 1, 2 2 3 4 3 Solving 1 , 0 The point of intersection is 1,2,3 lies

on third line 1 2 1 3 2 1 , 2

3 2 2k k h

h

16. Let the point on the parabola 22y x is

2

,2xP x

0,3Q

2f x PQ =22

2 32xx

2 21' 2 2 3 2 2 1 3

2 2 2x xf x x x x

3 4x x 2'' 3 4f x x

If 'f x =0

'' 2 8 0f , f x has minimum at 2x

The required point is 2,2

17. Given function is f x x

1'2

f xx

Now 9 4 1'

9 4 2f b f a

f cb a c

2 1 255/ 2 6.255 4

c cc

18. 2ln 1

xe Sinxx

Cosx x

2ln 1xe x SinxCosx

2

0 0

ln 1lim lim

x

x x

e x SinxCosxxx x

2

20 0

ln 1lim limx

x x

x Sinxxe Cosxx x

= 0 1 1 1 1

19. 22 0,3x x x x

Required area= 3 2

02x x x dx

32 33 2

00

332 3x xx x dx

27 27 92 3 2

20. If= 1dx xe e

2. 2 .xy If e Ifdx

22 .x x xye e e dx

323

x xye e C

223

x xy e Ce

21. n X n A B n A n B n A B =25+7-3=29

22. Sum= 14

7

3 2

12 3

nn n n

21 7.8 7.8.15 7.82 3

4 2 6 2

= 504 23. 2 , 2 , 2 , , , , ,N A I E X M T O (11 letters) Possibilities to form 4 letter words are as

follows (All 4 distiinct) = 8

4 1680P (2 same , 2 distinct) =

3 71 2

4! 7562!

C C

( 2 same, 2 same) = 32

4! 182!2!

C

Total = 1680+756+18 = 2454 24. 11cos 16 sin 3 log 2 cos 5sin 2

2 cos 5sinx x dx x x x cx

2, 3, 5

5 2 3 5 10


25. 227 56 1 6 11 6 48 811 5

dy x x x xdx

PHYSICS 26. 1

SS

V Vn nV

2S

sV Vn n

V

200 40160 40

VV

27. 1sin

B

A

CC C

8

8

2.4 10 12 10 sinc

Sin C 20 524 6

28. 1 1 2 2n n 260 5890 5460n 2 65n 29. The total volume of a charged conduction

is an equipotential surface and flux = 0ql

30. C= (mB) (2 l ) sinθ C= F(2 l ) sinθ

31. diE Mdt

541

500

E

32. 10 2100

Q

2 22 2 2

2 21 1 1

121100

U Q QU Q Q

21

1

1 100 10%QQ

10100

QQ final charge

33.

42

2 241

sin 60 / 2 18100sin 120 / 2 3

N NN

34. 1

c

b

II

35. ____ 1

/ 2hC E

2 ____ 2

/ 3hC E

Deviding (1),(2)

hC

36. 2

2PEM

hPC

37. 212

mm ev r reBe Bm

3

6

2 12 10210 0.6

VrvB

38. Heat lost = heat gained 5(540)+5(1)(100-40)=2ms (40-32) 2ms = 375 gram

39. 3PVVM

Given 424 10P , 310 10V , 320 10M

40. 52 110 48 2X

530 10.650

X

41. VL =V0, VC =2V0, VR=3V0 2

2L CR

V V V V

220 0 0100 9 2V V V

4 20 010 10 10 10V V

03 30 10 90RV V V 42. 1 2 cos90 / 2R P

21202 cos

2R P

43. 2 28 /S cm s 3 101 /S cm s 3 2 73 /S S cm s 44. F = 2Adv2

45. 212

w Y stain

46. 2

2 22

1 11 8 1 1 82 2

KmV mVR

21 42

mV J

21 11 62 2discE mV J

47. 0.1 0.32 2 ___ 1K

0.12TK

______(2)

48. 3 1.022 32

T R T R RT R T R


49. 2 22 14 4tV

2 2 2 21 1 6 1 0 32 2

w m v u J

50. w = T(2A)

CHEMISTRY 51. The following reaction occurs : 2 2 3 3

2 7 26 14 6 2 7Fe Cr O H Fe Cr H O From the above equation, we find that Mohr’s salt (FeSO4.(NH4)2SO4.6H2O) and dichromate reacts

6 : 1 molar ratio 52. Radial probability function curve for 1s is

53. structure of a molecule can be ascertained

by knowing the number of hybride bonds in the molecule. Thus

In 31: 5 3 0 0 42

NF H

Thus N in 3NO sp3 hybridized as 4 orbital are involved in bonding.

In 31: 5 0 0 1 32

NO H

Thus N in 3 :NO sp2 hybridized as 3 orbitals are involved in bonding.

In 31: 3 3 0 0 32

BF H

Thus B in BF3 is sp2 hybridized and 3 orbitals are involved in bonding

In 31: 6 3 0 0 42

H O H

Thus O in 3H O is sp3 hybridized and 3 orbital are involved in bonding

Thus, isostructural pairs are [NF3, H3O+] and 3 3, .NO BF

54. 2 2;a aP V b RT Here PV V

represents

The intermolecular forces. 55. . n

P CK K RT ∆n=2 - 4 = -2

5

21.44 10 ,

0.082 773P

C nKK

RT

(R in L. atm. K-1 mole-1)

56. Increasing size of cation decreases its polarization ability towards carbonate, making the compound more stable.

The increasing thermal stability is BeCO3<MgCO3<CaCO3<K2CO3 57. The stability of cabonium ion is influenced

by both resonance and inductive effect

+2CH

2NO

2NO Intensifies+ve chargeonbenzylcation

due to -I and -M effects

+2CH

Benzyl stableduetoresonance

+

2CH

chargeonCCl intensifies + ve

due to-Ieffect

Cl

+2CH

3OCH

more disperseddueto +M effect of the

-OCH group3

bemzylcation isPositive charge of

58.

3

2

1.O2.H O/Zn

E

CHO

CHO

2

KOH aq ,Δ-H O

aldol condensation

CHO

F 59. We known that surface acting agnets (i.e.

surfactants) such as soaps and detergents belong to the class of micelles. A miceller system when dissolved in water, dissociates to give ions. The anion consists of two parts. The polar groups such as (COO- or 4SO ) ion is water loving (i.e.hydrophilic) in nature. Its is called head of the species. The hydrocarbon chain which is quite big in size is water repelling (i.e. hydrophobic) in nature. It is called tail of the species. Above the critical concentration.

Note : It may also be noted that the critical concentration for micelle formation hydrocarbon chain the two surfacatnat.


Here the two anions that are formed are in case of ‘B’ (i.e. CH3 (CH2)11 3OSO ) and ‘C’ (i.e. CH3(CH2)6 COO-)

The molecular weight of hydrocarbon chain is more in case of “B” so it has lower value of critical concentration for micelle formation in aqueous solution.

60. Cell reaction : 2 2Zn Fe Zn Fe

2

02

0.0591 logcell cellZnE E

n Fe

2

03

0.0591 10log2 10

E E

0 0.05910.2905 0.2612

E

Or 0.261

0.02950.05910.261 log . 102 eq eqK or K

61. During the extraction of copper, iron is present in the ore as impurity (FeS).

The ore together with a little coke and silica is smelted ; FeS present as impurity in the ore is oxidized to iron oxide, which then reacts with silica to form fusible ferrous silicate which is removed as slag.

2 22 3 2 2 ;FeS O FeO SO

2 3

SlagFeO SiO FeSiO

62. On moving along a period from left to right I.E. increases and on moving down a group I.E. decreases. Hence correct order is :

Ba<Ca<Se<S<Ar 63.

0 3 1

4 2 3 2 43 3 3P NaOH H O P H NaH P O

5

3 4 3Na PO PH

reduction

Oxidation

64. Colour is due to d-d transitions. Coloured

compounds contain partly filled d-orbital. The oxidation state of copper in various

compounds is +1 and +2. In CuF2 it is in +2 oxidation state. In +2 state it configuration is

2 2 2 6 2 6 91 2 2 3 3 3Cu s s p s p d

3di.e. it has one unpaired electron due to this it is coloured (CuF2 possesses blue colur in crystalline form)

65. 2

.2 2

Alc KOH

NaNH

BrCH CHBr CH

CHBr CH CH

Elimination of HBr from CH2=CHBr requires a stronger base because here, Br acquires partial double bond character due to resonance.

66.

3HOCH

3O CH

H

Br 3OH CHBr

67.

..

..O

H

O

O

2RCH OH

O 2HOCH R

H

O 2OCH R

An acetal

68. This reaction is an example of “ Perkin

reaction” . The compound X should be (CH3CO)2O. In this step the carbanion is obtained by

removal of an α-H atom from a molecule of an acid anhydride the anion of the corresponding acid acting as a necessary base.

69. (i) Position (X) is most acidic due to – COOH group.

(ii) 3NH group at position Y is more acidic than at Z because of presence of electron withdraowing –COOH group in close proximity. Hence - 3NH group at position Z is least acidic.

70. Photochemical smog is caused by oxides of sulphur and nitrogen.

71. Depression in freezing pont, f fT i K m

Van’t Hoff factor, 11

ni , where n=

no. of ions produced by complete dissociation of 1 mole of HX.

2HX H X n 1 0.2 2 0.2 1.2

1i

[For 20% ionization. 20 0.2100

]

1.2 1.86 0.2 0.45 0.2fT m


Hence freezing point of solution is -0.45 0. 0F P water C 72. Enthlply change for in isothermal

reversible process is given by 2

1

100ln 2 8.314 2.303log10

VH nRV

1 138.3Jmol K 73. Overall order = sum of orders w.r.t each

reactant. Let the order be x and y for G and H

respectively Exp.No [G]

mole Litre-1

[H] mole litre-1

Rate (mole Litre-

time-1) 1 a b r 2 2a 2b 8r 3 2a b 2r

Applying x yr k G H we get, x=1 . y=2 For (1) and (3), the rate is doubled when

conc. Of G is doubled keeping that ofH constant i.e., rate G

1x From (2) and (3), y= 2 Overall order is 3. 74.

Rh Rh Rh

Cl Cl Cl3PPh3PPh

3PPh

CO

COCO 3NH 3NH 3NH The number of geometrical isomers is 3. 75. The basic group in the given form of lysine

is NH2 3 2 .not H and CO

*****


Paper Setters:

Subject Name of the Paper Setter Phone No Branch

MATHS-A RAVI SIR 7989242501 HYD DSNRB AC

MATHS-B A SRINIVAS RAO SIR 9618183020 HYD DSNRB AC

PHYSICS ESHWAR SIR 7989369608 HYD DSNRB AC

CHEMISTRY BHASKAR SIR 7386458167 HYD DSNRB AC

Paper Verifiers:

Subject Name of the Paper Verifier Phone No Branch

MATHS-A S THIRUPATHI 9849494828 KRMNG

MATHS-B E JAIPAL RAO 9966482846 KRMNG

PHYSICS CH MAHENDER 9920927759 KRMNG

CHEMISTRY M BIKSHAPATHI 9550747452 KRMNG

SR MPC JEE MAINS GT 6 EX DT 12-07-2020.pdf - Meluha ...

Documents