Practice Questions

Q27.Muon (μ−1) is negatively charged (|q| = |e|) with a mass mμ = 200 me , where me is the mass of the electron and e is the electronic charge. If μ−1 is bound to a proton to form a hydrogen like atom, identify the correct statements (A) Radius of the muonic orbit is 200 times smaller than that of the electron (B) the speed of the μ−1 in the nth orbit is 1 times that of the election in the nth orbit (C) The lonization energy of muonic atom 200 is 200 times more than that of an hydrogen atom (D) The momentum of the muon in the nth orbit is 200 times more than that of the electron (1) (A), (B), (D) (2) (B), (D) (3) (C),(D) (4) (A), (C), (D)

Q37.At 320 K, a gas A2 is 20 % dissociated to A(g) . The standard Gibbs free energy change at 320 K and 1 atm in J mol–1 is approximately: (R = 8 .314 JK–1 mol–1 ; ln 2 = 0 .693 ; ln 3 = 1 .098) (1) 1844 (2) 2068 (3) 4281 (4) 4763

Q44.When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p- aminophenol produced is: (1) 109.0 g (2) 98.1 g (3) 9.81 g (4) 10.9 g

Q45.The correct match between items of List-I and List-II is : (1) (A)-(r),(B)-(s), (C)-(p),(D)-(q) (2) (A)-(p),(B)-(s), (C)-(r),(D)-(q) (3) (A)-(r), (B)-(p), (C)-(q), (D)-(s) (4) (A)-(r),(B)-(p), (C)-(s),(D)-(q)

Q49. N2O5 decomposes to NO2 and O2 follows the first order kinetics. After 50 minutes, the pressure inside the vessel increases from 50 mm Hg to 87. 5 mm Hg . The pressure of the gaseous mixture after 100 minutes at constant temperature will be: (1) 136. 5 mm Hg (2) 106. 25 mm Hg (3) 175. 0 mm Hg (4) 116. 25 mm Hg

Q49.When XO2 is fused with an alkali metal hydroxide in presence of an oxidizing agent such as KNO3 ; a dark green product is formed which disproportionate in acidic solution to afford a dark purple solution. X is: JEE Main 2018 (16 Apr Online) JEE Main Previous Year Paper (1) Mn (2) Cr (3) V (4) Ti

Q49.How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27. 66 g of diborane? (Atomic weight of B = 10. 8 u) (1) 1. 6 hours (2) 6. 4 hours (3) 0. 8 hours (4) 3. 2 hours

Q52. N2O5 decomposes to NO2 and O2 and follows first order kinetics. After 50 minutes, the pressure inside the vessel increases from 50 mm Hg to 87.5 mm Hg . The pressure of the gaseous mixture after 100 minutes at constant temperature will be ______. (1) 136.25 mm Hg (2) 106.25 mm Hg (3) 175.0 mm Hg (4) 116.25 mm Hg

Q52.Consider the following reaction and statements: [Co (NH3)4 Br2]+ + Br−→[Co (NH3)3 Br3] + NH3 (i) Two isomers are produced if the reactant complex ion is a cis-isomer. (ii) Two isomers are produced if the reactant complex ion is a trans-isomer. (iii) Only one isomer is produced if the reactant complex ion is a trans-isomer. (iv) Only one isomer is produced if the reactant complex ion is a cis-isomer. The correct statements are (1) (ii) and (iv) (2) (i) and (ii) (3) (i) and (iii) (4) (iii) and (iv)

Q53.The correct combination is (1) [NiCl4]2−− Square planar; [Ni (CN)4]2−− (2) [Ni (CN)4]2−− tetrahedral; [Ni (CO)4]2−− paramagnetic paramagnetic (3) [NiCl4]2−− paramagnetic; [Ni (CO)4]− (4) [NiCl4]2−− diamagnetic; [Ni (CO)4]− square- tetrahedral planar

Q54.The major product of the following reaction is: JEE Main 2018 (16 Apr Online) JEE Main Previous Year Paper (1) (2) (3) (4)

Q55.The total number of possible isomers for squareplanar [Pt(Cl) (NO2) (NO3)(SCN)]2− is: (1) 16 (2) 12 (3) 8 (4) 24

Q57.The reagent(s) required for the following conversion are: (1) (i) NaBH4 , (ii) Raney Ni/H2 , (iii) H3O+ (2) (i) LiAlH4 , (ii) H3O+ (3) (i) B2H6 , (ii) DIBAL −H, (iii) H3O+ (4) (i) B2H6 , (ii) SnCl2/HCl, (iii) H3O+

Q63.The set of all α ∈R, for which w = 1+(1−8α)z1−z is a purely imaginary number, for all and Re(z) ≠1 , is : (1) {0} (2) {0, 14 , −14 } (3) equal to R (4) an empty set

Q66.If n is the degree of the polynomial, 1 8 1 8 + [ √5x3 + 1 −√5x3 −1 ] [ √5x3 + 1 + √5x3 −1 ] and m is the coefficient of xn in it, then the ordered pair (n, m) is equal to (1) (12, (20)4) (2) (8, 5(10)4) (3) (24, (10)8) (4) (12, 8(10)4) JEE Main 2018 (15 Apr Shift 1 Online) JEE Main Previous Year Paper

Q67.If n is the degree of the polynomial, 8 8 m is the coefficient of xn + [ √5x3+1−√5x3−12 ] [ √5x3+1+√5x3−12 ] and in it, then the ordered pair (n, m) is equal to (1) (8, 5(10)4) (2) (12, 8(10)4) (3) (12, (20)4) (4) (24, (10)8)

Q69.The sides of a rhombus ABCD are parallel to the lines, x −y + 2 = 0 and 7x −y + 3 = 0. If the diagonals of the rhombus intersect at P(1, 2) and the vertex A (different from the origin) is on the y axis, then the ordinate of A is (1) 2 (2) 7 4 (3) 7 (4) 5 2 2

Q69.Two parabolas with a common vertex and with axes along the x-axis and y-axis respectively, intersect each other in the first quadrant. If the length of the latus rectum of each parabola is 3 , then the equation of the common tangent to the two parabolas is : (1) 3(x + y) + 4 = 0 (2) 8(2x + y) + 3 = 0 (3) x + 2y + 3 = 0 (4) 4(x + y) + 3 = 0 JEE Main 2018 (15 Apr) JEE Main Previous Year Paper cos θ, √3 sin

Q70.Tangent and normal are drawn at P(16, 16) on the parabola y2 = 16x, which intersect the axis of the parabola at A & B, respectively. If C is the center of the circle through the points P, A & B and ∠CPB = θ, then a value of tan θ is: (1) 4 (2) 1 3 2 (3) 2 (4) 3

Q70.If β is one of the angles between the normals to the ellipse x2 + 3y2 = 9 at the points (3 θ) and θ ∈(0, π2 ); then 2sincot2θβ is equal to : (−3 sin θ, √3 cos θ); (1) 1 (2) √3 √3 4 (3) 2 (4) √2 √3

Q70.Two parabolas with a common vertex and with axes along x-axis and y-axis, respectively, intersect each other in the first quadrant. if the length of the latus rectum of each parabola is 3 , then the equation of the common tangent to the two parabolas is? (1) 3(x + y) + 4 = 0 (2) 8(2x + y) + 3 = 0 (3) 4(x + y) + 3 = 0 (4) x + 2y + 3 = 0

Q70.Let P be a point on the parabola x2 = 4y. If the distance of P from the center of the circle x2 + y2 + 6x + 8 = 0 is minimum, then the equation of the tangent to the parabola at P is (1) x + y + 1 = 0 (2) x + 4y −2 = 0 (3) x + 2y = 0 (4) x −y + 3 = 0

Q71.If β is one of the angles between the normals to the ellipse, x2 + 3y2 = 9 at the points (3 cos θ, √3 sin θ) and (−3 sin θ, √3 cos θ); ∈(0, π2 ); then 2sincot2θβ is equal to (1) √2 (2) 2 √3 (3) 1 (4) √3 √3 4

Q72.If the tangents drawn to the hyperbola 4y2 = x2+ 1 intersect the co-ordinate axes at the distinct points A and B, then the locus of the mid point of AB is (1) x2 −4y2 + 16x2y2 = 0 (2) 4x2 −y2 + 16x2y2 = 0 (3) 4x2 −y2 −16x2y2 = 0 (4) x2 −4y2 −16x2y2 = 0

Q72.A normal to the hyperbola, 4x2 −9y2 = 36 meets the co-ordinate axes x and y at A and B, respectively. If the parallelogram OABP(O being the origin) is formed, then the locus of P is (1) 4x2 −9y2 = 121 (2) 4x2 + 9y2 = 121 (3) 9x2 −4y2 = 169 (4) 9x2 + 4y2 = 169