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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
ChemistrySingle Correct Questions +4 | 1
1. Which of the following salts is the most basic in aqueous solution?(1 )(2 )(3 )
(4 )
2. Which of the following compounds will be suitable for Kjeldahl's method for nitrogen estimation?
(1 )
(2 )
(3 )
(4 )
3. Which of the following are Lewis acids?(1) and
(2) and
(3) and
(4) and
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
4. Phenol on treatment with in the presence of followed by acidification produces compound as the majorproduct. on treatment with in the presence of catalytic amount of produces :
5. An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?(1 ) Base Strong; Acid Strong; End point Pinkish red to yellow(2) Base Weak; Acid Strong; End point Yellow to pinkish red(3 ) Base Strong; Acid Strong; End point Pink to colourless(4 ) Base Weak; Acid Strong; End point Colourless to pink
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
6. An aqueous solution contains and If the equilibrium constants for the formation of from is and that of from ions is then the concentration of ions in aqueoussolution is:
7. The combustion of benzene gives and Given that heat of combustion of benzene at constantvolume is at heat of combustion (in ) of benzene at constant pressure will be:
8. The compound that does not produce nitrogen gas by the thermal decomposition is:
9. How long (approximate) should water be electrolysed by passing through amperes current so that the oxygenreleased can completely burn of diborane?(Atomic weight of )
hours
hours
hours
hours
10. Total number of lone pair of electrons in ion is:6
9
12
3
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
11. When metal 'M' is treated with NaOH, a white gelatinous precipitate 'X' is obtained, which is soluble in excess ofNaOH. Compound 'X' when heated strongly gives an oxide which is used in chromatography as an adsorbent. Themetal 'M' is :
Ca
Al
Fe
Zn
12. According to molecular orbital theory, which of the following will not be a viable molecule ?
13. The increasing order of basicity of the following compounds is :
(b) < (a) < (c) < (d)
(b) < (a) < (d) < (c)
(d) < (b) < (a) < (c)
(a) < (b) < (c) < (d)
14. Which type of 'defect' has the presence of cations in the interstitial sites ?Vacancy defect
Frenkel defect
Metal deficiency defect
Schottky defect.
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
15. Which of the following compounds contain(s) no covalent bond(s) ?
16. The oxidation states of Cr in
17. Hydrogen peroxide oxidises in acidic medium but reduces to in alkaline medium. The other products respectively are:
18. Glucose on prolonged heating with HI gives :1Hexene
Hexanoic acid
6iodohexanal
nHexane.
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
19. The predominant form of histamine present in human blood is (pKa, Histidine = 6.0)
20. The recommended concentration of fluoride ion in drinking water is up to 1ppm as fluoride ion is required to maketeeth enamel harder by converting.
21. Consider the following reaction and statements:
(I) Two isomer are produced if the reactant complex ion is a cisisomer.(II) Two isomers are produced if the reactant complex ion is transisomer.(III) Only one isomers are produced if the reactant complex ion is transisomer.(IV) Only one isomers are produced if the reactant complex ion is cisisomer.
(I) and (III)
(III) and (IV)
(II) and (IV)
(I) and (II)
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
22. The transalkenes are formed by the reduction of alkynes with :
23. The ratio of mass percent of C and H of an organic compound is 6: 1. If one molecule of the abovecompound contains half as much oxygen as required to burn one molecule of compound completely to and The empirical formula of compound is:
24. Phenol reacts with methyl chloroformate in the presence of to form product A. A reacts with to formproduct B. A and B are respectively :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
25. The major product of the following reaction is:
26. Which of the following lines correctly show the temperature dependence of equilibrium constant, K, for an exothermicreaction?
B and C
C and D
A and D
A and B
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
27. The major product formed in the following reaction is:
28. An aqueous solution contain an unknown concentration of When 50 mL of a 1M solution of is added, just begins to precipitate. The final volume is 500 mL. The solubility product of is What is
the original concentration of
29. At 518oC, the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of was when 5% had reacted and when 33% had reacted. The order of the reaction is:
3
1
0
2
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
30. For 1 molal aqueous solution of the following compounds, which one will show the highest freezing point?
Mathematics
31. The integral is equal to :
32. Tangents are drawn to the hyperbola at the points If these tangents intersect at the point then the area (in sq. units) of is :
33. Tangent and normal are drawn at on the parabola which intersect the axis of the parabola at , respectively. If is the centre of the circle through the points and then the value
of is :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
34. Let be a vector coplanar with the vectors If is perpendicular to then is equal to :
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35. If are the distinct roots, of the equation is equal to :
36. Let be the roots of the quadratic equation Then the area (in sq. units) bounded by the curve and the lines
37. The sum of the coefficients of all odd degree terms in the expansion of is :
38. Let be in A.P. such that If
then is equal to :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
39. If then the standard deviation of the 9 items is :
40. is a triangular park with A T.V. towar stands at the midpoint of If the angle ofelevation of the top of the tower at and are respectively then the height of the tower (in m)is :
41. Two sets A and B are as under :
. Then :
(an empty set)
Neither nor
42. From 6 different novels and 3 different dictionaries, 4 novels and 1 dictionary are to be selected and arranged in a rowon a shelf so that the dictionary is always in the middle. The number of such arrangements is :
Less than 500
At least 500 but less than 750
At least 750 but less than 1000
At least 1000
43. Let and , . If then the local minimum value of is:
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
44. For each , let be the greatest integer less than or equal to . Then
is equal to 15
is equal to 120
Does not exist (in R)
Is equal to 0
45. The value of is :
46. A bag contains 4 red and 6 black balls. A ball is drawn at random from the bag, its colour is obsreved and this ballalong with two additional balls of the same colour are returned to the bag. If now a ball is drawn at random from thebag, then the probability that this drawn ball is red, is :
47. The length of the projection of the line segment joining the points and on the plane, is :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
48. If sum of all the solutions of the equation in is , then is
equal to :
49. A straight line through a fixed point (2, 3) intersects the coordinate axes at distinct points P and Q. If O is the origin andthe rectangle OPRQ is completed, then the locus of R is :
50. Let A be the sum of the first 20 terms and B be the sum of the first 40 terms of the series
If , then is equal to :248
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232
51. If the curves intersect each other at right angles, then the value of is :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
52. Let the orthocentre and centroid of a triangle be and respectively. If is the circumcentre of thistriangle, then the radius of the circle having line segment AC as diameter, is :
53. Let . Then the set is equal to :
(an empty set)
54. If then the ordered pair is equal to :
55. The Boolean expression is equivalent to :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
56. If the system of linear equations
has a nonzero solution then is equal to :
57. Let . Then
contains exactly one element
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58. If the tangent at to the curve touches the circle then the value of is:
59. Let be the solution of the differential equation
If is equal to :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
60. If is the line of intersection of the planes and is the line ofintersection of the planes then the distance of the origin from the plane,containing the lines is :
Physics
61. The angular width of the central maximum in a single slit diffraction pattern is 60o. The width of the slit is The slitis illuminated by monochromatic plane waves. If another slit of same width is made near it, Young's fringes can beobserved on a screen placed at a distance 50 cm from the slits. If the observed fringe width is 1 cm, what is slitseparation distance?(i.e. distance between the centres of each slit.)
62. An electron from various excited states of hydrogen atom emit radiation to come to ground state. Let be the deBroglie wavelength of the electron in the nth state and the ground state respectively. Let be the wavelength of theemitted photon in the transition from the nth state to ground state. For large are constants
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
63. The reading of the ammeter for a silicon diode in the given circuit is:
15 mA
11.5 mA
13.5 mA
0
64. The density of a material in the shape of a cube is determined by measuring three sides of the cube and its mass. Ifthe relative errors in measuring the mass and length are respectively 1.5% and 1%, the maximum error in determiningthe density is:
3.5%
4.5%
6%
2.5%
65. An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii respectively in a uniform magnetic field The relation between is:
66. Three concentric metals shells and of respective radii and have surface charge densities and respectively. The potential of shell is:
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
67. Two masses and connected by an inextensible string over a frictionless pulley, are moving asshown in the figure. The coefficient of friction of horizontal surface is 0.15. The minimum weight that should be puton top of to stop the motion is:
68. A particle is moving in a circular path of radius under the action of an attractive potential Its total energy is:
Zero
69. A parallel plate capacitor of capacitance is connected to a battery of emf If a dielectric material of dielectricconstant is inserted between the plates, the magnitude of the induced charge will be:
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
70. A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of What isthe force constant of the bonds connecting one atom with the other? (Mole wt. of silver and Avagadro number
)
71. It is found that if a neutron suffers an elastic collinear collision with deuterium at rest, fractional loss of its energy is while for its similar collision with carbon nucleus at rest, fractional loss of energy is The values of and arerespectively:
72. The dipole moment of a circular loop carrying a current is and the magnetic field at the centre of the loop is When the dipole moment is doubled by keeping the current constant, the magnetic field at the center of the loop is The ratio is:
73. In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of thecell are connected across of the potentiometer wire. If the cell is shunted by a resistance of a balance isfound when the cell is connected across of the wire. Find the internal resistance of the cell.
74. A telephonic communication service is working at carrier frequency of Only 10% of it is utilized fortransmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidthof
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
75. Unpolarized light of intensity passes through an ideal polarizer Another identical polarizer is placed behind The intensity of light beyond is found to be Now another identical polarizer is placed between and The
intensity beyond is now found to be The angle between polarizer and
76. On interchanging the resistances, the balance point of a meter bridge shifts to the left by The resistance of theirseries combination is How much was the resistance on the left slot before interchanging the resistances?
77. From a uniform circular disc of radius and mass a small disc of radius is removed as shown in the figure.
The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing throughcenter of disc is:
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
78. In a collinear collision, a particle with an initial speed strikes a stationary particle of the same mass. If the final totalkinetic energy is 50% greater than the original kinetic energy, the magnitude of the relative velocity between the twoparticles, after collision, is:
79. An EM wave from air enters a medium. The electric fields are in air and in medium, where the wave number and frequency refer to their values in air. The
medium is nonmagnetic. If and refer to relative permittivities of air and medium respectively, which of thefollowing options is correct?
80. For an RLC circuit driven with voltage of amplitude and frequency the current exibits resonance. The
quality factor, is given by:
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
81. All the graphs below are intended to represent the same motion.One of them does it incorrectly. Pick it up.
82. Two batteries with e.m.f. and are connected in parallel across a load resistor of . The internal resistancesof the two batteries are and respectively. The voltage across the load lies between :
83. A particle is moving with a uniform speed in a circular orbit of radius in a central force inversely proportional to the power of . If the period of rotation of the particle is then :
for any
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
84. If the series limit frequency of the Lyman series is then the series limit frequency of the Pfund series is :
85. In an a.c. circuit, the instantaneous e.m.f. and current are given by
In one cycle of a.c., the average power consumed by the circuit and the wattless current are, respectively :
86. Two moles of an ideal monoatomic gas occupies a volume at . The gas expands adiabatically to a volume .Calculate (a) the final temperature of the gas and (b) change in its internal energy.
(a) (b)
(a) (b)
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87. A solid sphere of radius made of a soft material of bulk modulus is surrounded by a liquid in a cylindrical container.A massless piston of area a floats on the surface of the liquid, covering entire cross section of cylindrical container.When a mass is placed on the surface of the piston to compress the liquid, the fractional decrement in the radius of
the sphere, is :
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Rao IIT Academy / JEE MAIN OFFICIAL EXAM 2018 / CODE C / QP
88. A granite rod of length is clamped at its middle point and it set into longitudinal vibrations. The density of graniteis and its Young's modulus is . What will be the fundamental frequency of thelongitudinal vibrations ?
89. The mass of a hydrogen molecule is . If hydrogen molecules strike, per second, a fixed wall ofarea at an angle of to the normal, and rebound elastically with a speed of then the pressure on thewall is nearly :
90. Seven identical circular planar disks, each of mass and radius are welded symmetrically as shown. The momentof inertia of the arrangement about the axis normal to the plane and passing through the point is :
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