Practice Questions

Q61.The calculated spin-only magnetic moments of K3 [Fe(OH)6] and K4 [Fe(OH)6] respectively are : (1) 3.87 and 4.90 B.M. (2) 4.90 and 5.92 B.M. (3) 4.90 and 4.90 B.M. (4) 5.92 and 4.90 B.M.

Q61.Given below are two statements about X-ray spectra of elements : Statement (I) : A plot of √v ( v = frequency of X -rays emitted) vs atomic mass is a straight line. Statement (II) : A plot of v(v = frequency of X -rays emitted) vs atomic number is a straight line. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Statement I is false but Statement II is true (3) Both Statement I and Statement II are false (4) Statement I is true but Statement II is false

Q61. CrCl3 ⋅xNH3 can exist as a complex. 0.1 molal aqueous solution of this complex shows a depression in freezing point of 0.558∘C. Assuming 100% ionisation of this complex and coordination number of Cr is 6 , the complex will be (Given Kf = 1.86 K kg mol−1 ) (1) [Cr(NH3)5Cl]Cl2 (2) [Cr(NH3)6]Cl3 (3) [Cr(NH3)3Cl3] (4) [Cr(NH3)4Cl2]Cl

Q62.In the given structure, number of sp and sp2 hybridized carbon atoms present respectively are : (1) 4 and 5 (2) 3 and 5 (3) 3 and 6 (4) 4 and 6 2025 (24 Jan Shift 2) JEE Main Previous Year Paper

Q62. HNO3 H2SO4 (1) Ammoniumacetate −−−Identify A, B and C in the given below reaction sequence A → Pb(NO3)2 → B → (2) Acetic acid (3) K2CrO4 (1) PbCl2, PbSO4, PbCrO4 (2) PbS, PbSO4, Pb(CH3COO)2 (3) PbCl2, Pb(SO4)2, PbCrO4 (4) PbS, PbSO4, PbCrO4

Q62.Which of the following statement is not true for radioactive decay? (1) Decay constant increases with increase in (2) Amount of radioactive substance remained after temperature. three half lives is 1 th of original amount. 8 (3) Decay constant does not depend upon (4) Half life is ln 2 times of rate constant1 . temperature.

Q62.Match the LIST-I with LIST-II Choose the correct answer from the options given below: (1) A-II, B-III, C-I, D-IV (2) A-III, B-IV, C-I, D-II (3) A-IV, B-I, C-II, D-III (4) A-II, B-III, C-IV, D-I

Q62.The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is : (1) A2O (2) A2O3 (3) AO2 (4) AO

Q62.Given below are two statements : Statement (I) : A spectral line will be observed for a 2px →2py transition. Statement (II) : 2Px and 2py are degenerate orbitals. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Statement I is false but Statement II is true (3) Both Statement I and Statement II are false (4) Statement I is true but Statement II is false

Q62.Which of the following statements are NOT true about the periodic table? A. The properties of elements are function of atomic weights. B. The properties of elements are function of atomic numbers. C. Elements having similar outer electronic configurations are arranged in same period. D. An element's location reflects the quantum numbers of the last filled orbital. E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is being filled. Choose the correct answer from the options given below: (1) A, C and E Only (2) A and E Only (3) B, C and E Only (4) D and E Only

Q62.Which of the following happens when NH4OH is added gradually to the solution containing 1 M A2+ and 1MB3+ ions? Given : Ksp [A(OH)2] = 9 × 10−10 and Ksp [B(OH)3] = 27 × 10−18 at 298 K . (1) Both A(OH)2 and B(OH)3 do not show (2) A(OH)2 will precipitate before B(OH)3 precipitation with NH4OH (3) B(OH)3 will precipitate before A(OH)2 (4) A(OH)2 and B(OH)3 will precipitate together excess HCHO alkali−

Q62.Consider an elementary reaction A(g) + B(g) →C(g) + D(g) If the volume of reaction mixture is suddenly reduced to 1 of its initial volume, the reaction rate will become ' x ' times of the original reaction rate. The 3 value of x is : (1) 3 (2) 19 (3) 9 (4) 13

Q62.If a0 is denoted as the Bohr radius of hydrogen atom, then what is the de-Broglie wavelength (λ) of the electron present in the second orbit of hydrogen atom? [n : any integer] (1) 8πa0 (2) 2a0 n nπ (3) 4n (4) 4πa0 πa0 n

Q63.Given below are two statements : Statement (I) : An element in the extreme left of the periodic table forms acidic oxides. Statement (II) : Acid is formed during the reaction between water and oxide of a reactive element present in the extreme right of the periodic table. In the light of the above statements, choose the correct answer from the options given below : (1) Statement I is true but Statement II is false (2) Both Statement I and Statement II are true (3) Both Statement I and Statement II are false (4) Statement I is false but Statement II is true 2025 (22 Jan Shift 2) JEE Main Previous Year Paper

Q63.Given below are two statements I and II. Statement I: Dumas method is used for estimation of "Nitrogen" in an organic compound. Statement II: Dumas method involves the formation of ammonium sulphate by heating the organic compound with conc H2SO4 . In the light of the above statements, choose the correct answer from the options given below (1) Statement I is true but Statement II is false (2) Both Statement I and Statement II are false (3) Statement I is false but Statement II is true (4) Both Statement I and Statement II are true

Q63.Given below are two statements : Statement (I) : The boiling points of alcohols and phenols increase with increase in the number of C-atoms. Statement (II) : The boiling points of alcohols and phenols are higher in comparison to other class of compounds such as ethers, haloalkanes. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are false (2) Both Statement I and Statement II are true (3) Statement I is false but Statement II is true (4) Statement I is true but Statement II is false

Q63.Given below are two statements: Statement I: In the oxalic acid vs KMnO4 (in the presence of dil H2SO4 ) titration the solution needs to be heated initially to 60∘C, but no heating is required in Ferrous ammonium sulphate (FAS) vs KMnO4 titration (in the presence of dil H2SO4 ) Statement II: In oxalic acid vs KMnO4 titration, the initial formation of MnSO4 takes place at high temperature, which then acts as catalyst for further reaction. In the case of FAS vs KMnO4 , heating oxidizes Fe2+ into Fe3+ by oxygen of air and error may be introduced in the experiment. In the light of the above statements, choose the correct answer from the options given below (1) Both Statement I and Statement II are false (2) Both Statement I and Statement II are true (3) Statement I is false but Statement II is true (4) Statement I is true but Statement II is false 2025 (28 Jan Shift 1) JEE Main Previous Year Paper

Q63. Match List - I with List - II. Choose the correct answer from the options given below : (1) (A)-(II), (B)-(III), (C)-(IV), (D)-(I) (2) (A)-(II), (B)-(III), (C)-(I), (D)-(IV) (3) (A)-(III), (B)-(II), (C)-(I), (D)-(IV) (4) (A)-(III), (B)-(II), (C)-(IV), (D)-(I)

Q63. The products formed in the following reaction sequence are : (1) (2) , CH3 −CHO , CH3 −COOH (3) (4) , CH3 −CHO

Q63.The major product of the following reaction is: CH3CH2CH = O → ? reflux (1) (2) (3) (4)

Q63.The product B formed in the following reaction sequence is : (1) (2) (3) (4)

Q63.Total number of sigma ( σ ) and pi(π) bonds respectively present in hex-1-en-4-yne are : (1) 3 and 13 (2) 11 and 3 (3) 13 and 3 (4) 14 and 3

Q63. Given below are two statements : In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Statement I is false but Statement II is true (3) Statement I is true but Statement II is false (4) Both Statement I and Statement II are false

Q64.First ionisation enthalpy values of first four group 15 elements are given below. Choose the correct value for the element that is a main component of apatite family : (1) 1402 kJ mol−1 (2) 834 kJ mol−1 (3) 1012 kJ mol−1 (4) 947 kJ mol−1

Q64. Residue (A) + HCl (dil) → Compound (B) Structure of residue (A) and compound (B) formed respectively is : (1) (2) (3) (4)