Practice Questions

Q50.The rate of a chemical reaction doubles for every 10∘C rise of temperature. If the temperature is raised by 50∘C, the rate of the reaction increases by about : (1) 24 times (2) 32 times (3) 64 times (4) 10 times

Q51.Which of the following statements regarding sulphur is incorrect? (1) The vapour at 200∘C consists mostly of S8 rings (2) At 600∘C the gas mainly consists of S2 molecules (3) The oxidation state of sulphur is never less than (4) S2 molecule is paramagnetic. +4 in its compounds

Q52.The structure of IF7 is : (1) trigonal bipyramid (2) octahedral (3) pentagonal bipyramid (4) square pyramid

Q53.In context of the lanthanoids, which of the following statements is not correct ? (1) All the members exhibit +3 oxidation state (2) Because of similar properties the separation of lanthanoids is not easy. (3) Availability of 4f electrons results in the (4) There is a gradual decrease in the radii of the formation of compounds in +4 state for all the members with increasing atomic number in the members of the series. series.

Q54.The outer electron configuration of Gd (Atomic No : 64 is : (1) 4f 85d06s2 (2) 4f 45d46s2 (3) 4f 75d16s2 (4) 4f 34d56s2

Q55.Which of the following facts about the complex [Cr(NH3)6]Cl3 s wrong ? (1) The complex is paramagnetic (2) The complex is an outer orbital complex (3) The complex gives white precipitate with silver (4) The complex involves d2sp3 hybridization and is nitrate solution octahedral in shape.

Q56.Phenol is heated with a solution of mixture of KBr and KBrO3 . The major product obtained in the above reaction is (1) 3-Bromophenol (2) 4-Bromophenol (3) 2, 4, 6- Tribromophenol (4) 2-Bromophenol

Q57.Sodium ethoxide has reacted with ethanoyl chloride. The compound that is produced in the above reaction is : (1) 2-Butanone (2) Ethyl chloride (3) Ethyl ethanoate (4) Diethyl ether

Q58.Trichloroacetaldehyde was subjected to Cannizzaro's reaction by using NaOH. The mixture of the products contains sodium trichloroacetate and another compound. The other compound is : JEE Main 2011 JEE Main Previous Year Paper (1) Trichloromethanol (2) 2, 2, 2-Trichloropropanol (3) Chloroform (4) 2, 2, 2-Trichloroethanol

Q59.Silver Mirror test is given by which one of the following compounds ? (1) Acetone (2) Formaldehyde (3) Benzophenone (4) None of these

Q60.The presence or absence of hydroxyl group on which carbon atom of sugar differentiates RNA and DNA ? (1) 2nd (2) 3rd (3) 4th (4) 1st

Q61.Let α, β be real and z be a complex number. If z2 + αz + β = 0 has two distinct roots on the line Re z = 1, then it is necessary that (1) β ∈(−1, 0) (2) |β| = 1 (3) β ∈(1, ∞) (4) β ∈(0, 1)

Q62.If ω(≠1) is a cube root of unity, and (1 + ω)7 = A + Bω. Then (A, B) equals (1) (1, 1) (2) (1, 0) (3) (−1, 1) (4) (0, 1)

Q63.This question has Statement −1 and Statement −2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement - 1 : The number of ways of distributing 10 identical balls in 4 distinct boxes such that no box is empty is 9C3 Statement-2: The number of ways of choosing any 3 places from 9 different places is 9C3 . (1) Statement −1 is true, Statement −2 is true; (2) Statement −1 is true, Statement −2 is false. Statement −2 is not a correct explanation for Statement −1 (3) Statement −1 is false, Statement- 2 is true. (4) Statement −1 is true, Statement −2 is true; Statement −2 is a correct explanation for Statement −1

Q64.A man saves Rs. 200 in each of the first three months of his service. In each of the subsequent months his saving increases by Rs. 40 more than the saving of immediately previous month. His total saving from the start of service will be Rs. 11040 after (1) 19 months (2) 20 months (3) 21 months (4) 18 months

Q65.The coefficient of x7 in the expansion of (1 −x −x2 + x3) 6 is (1) −132 (2) −144 (3) 132 (4) 144

Q66.If A = sin2 x + cos4 x, then for all real x (1) 13 16 ≤A ≤1 (2) 1 ≤A ≤2 (3) 3 4 ≤A ≤1316 (4) 43 ≤A ≤1 JEE Main 2011 JEE Main Previous Year Paper

Q67.The lines L1 : y −x = 0 and L2 : 2x + y = 0 intersect the line L3 : y + 2 = 0 at P and Q respectively. The bisector of the acute angle between L1 and L2 intersect L3 at R. This question has Statement −1 and Statement −2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement-1 : The ratio PR : RQ equals 2√2 : √5 . Statement-2 : In any triangle, bisector of an angle divides the triangle into two similar triangles. (1) Statement −1 is true, Statement −2 is true; (2) Statement −1 is true, Statement- 2 is false. Statement −2 is not a correct explanation for Statement −1 (3) Statement −1 is false, Statement- 2 is true. (4) Statement −1 is true, Statement −2 is true; Statement −2 is a correct explanation for Statement −1

Q68.The two circles x2 + y2 = ax and x2 + y2 = c2(c > 0) touch each other if (1) |a| = c (2) a = 2c (3) |a| = 2c (4) 2|a| = c

Q69.Equation of the ellipse whose axes are the axes of coordinates and which passes through the point (−3, 1) and has eccentricity is √25 (1) 5x2 + 3y2 −48 = 0 (2) 3x2 + 5y2 −15 = 0 (3) 5x2 + 3y2 −32 = 0 (4) 3x2 + 5y2 −32 = 0 Q70.$$ \lim _{x \rightarrow 2}\left(\frac{\sqrt{1-\cos \{2(x-2)\}}}{x-2}\right) (1) equals √2 (2) equals −√2 (3) equals 1 (4) does not exist √2

Q71.Consider the following statements P : Suman is brilliant Q : Suman is rich R : Suman is honest The negation of the statement "Suman is brilliant and dishonest if and only if Suman is rich" can be expressed as (1) ∼(Q ↔(P∧∼R)) (2) ∼Q ↔∼P ∧R (3) ∼(P∧∼R) ↔Q (4) ∼P ∧(Q ↔∼R)

Q72.If the mean deviation about the median of the numbers a, 2a, … , 50a is 50 , then |a| equals (1) 3 (2) 4 (3) 5 (4) 2

Q73.Let R be the set of real numbers This question has Statement −1 and Statement −2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement-1 : A = {(x, y) ∈R × R : y −x is an integer } is an equivalence relation on R. Statement-2 : B = {(x, y) ∈R × R : x = αy for some rational number α} is an equivalence relation on R. (1) Statement −1 is true, Statement −2 is true; (2) Statement −1 is true, Statement- 2 is false. Statement −2 is not a correct explanation for Statement −1 (3) Statement −1 is false, Statement −2 is true. (4) Statement −1 is true, Statement −2 is true; Statement −2 is a correct explanation for Statement −1 JEE Main 2011 JEE Main Previous Year Paper

Q74.Let A and B be two symmetric matrices of order 3 . This question has Statement −1 and Statement −2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement −1 : A(BA) and (AB)A are symmetric matrices. Statement - 2 : AB is symmetric matrix if matrix multiplication of A and B is commutative. (1) Statement −1 is true, Statement −2 is true; (2) Statement −1 is true, Statement −2 is false. Statement −2 is not a correct explanation for Statement −1 (3) Statement −1 is false, Statement- 2 is true. (4) Statement −1 is true, Statement −2 is true; Statement −2 is a correct explanation for Statement −1

Q75.The number of values of k for which the linear equations 4x + ky + 2z = 0; kx + 4y + z = 0; 2x + 2y + z = 0 possess a non-zero solution is (1) 2 (2) 1 (3) zero (4) 3