Practice Questions
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Q44.While preparing crystals of Mohr's salt, dil H2SO4 is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil H2SO4 is added here to : (1) prevent the hydrolysis of ferrous sulphate (2) prevent the hydrolysis of ammonium sulphate (3) make the medium strongly acidic (4) increase the rate of formation of crystals
Q45.A first row transition metal in its +2 oxidation state has a spin-only magnetic moment value of 3.86BM. The atomic number of the metal is (1) 26 (2) 25 (3) 23 (4) 22
Q45.Which of the following compounds show colour due to d - d transition? (1) CuSO4 Β· 5H2O (2) K2Cr2O7 (3) K2CrO4 (4) KMnO4
Q45.The number of complexes from the following with no electrons in the t2 orbital is TiCl4, [MnO4]β, [FeO4]2β, [FeCl4]β, [CoCl4]2β JEE Main 2024 (05 Apr Shift 2) JEE Main Previous Year Paper (1) 1 (2) 4 (3) 3 (4) 2
Q45.Given below are two statements: Statement (I): A solution of NiH2O6 2 + is green in colour. Statement (II): A solution of Ni ( CN 2 - is colourless. ) 4 In the light of the above statements, choose the most appropriate answer from the options given below: (1) Both Statement I and Statement II are incorrect (2) Both Statement I and Statement II are correct (3) Statement I is incorrect but Statement II is (4) Statement I is correct but Statement II is correct incorrect
Q45.he following complexes [CoCl(NH3)5]2+ , [Co(CN)6]3β , [Co(NH3)5 (H2O)]3+ , [Cu(H2O)4]2+ The correct (A) (B) (C) (D) order of A, B, C and D in terms of wavenumber of light absorbed is : (1) C < D < A < B (2) B < C < A < D (3) A < C < B < D (4) D < A < C < B
Q45.Match List I with List II LIST β II LIST β I (Electronic (Complex ion) Configuration A. πΆππ»2π6 3 + I. π‘2π2 ππ0 B. πΉππ»2π6 3 + II. π‘2π3 ππ0 C. πππ»2π6 2 + III. π‘2π3 ππ2 D. ππ»2π6 3 + IV. π‘2π6 ππ2 Choose the correct answer from the options given below : (1) A-III, B-II, C-IV, D-I (2) A-IV, B-I, C-II, D-III (3) A-IV, B-III, C-I, D-II (4) A-II, B-III, C-IV, D-I
Q45.The molecule/ion with square pyramidal shape is: (1) Ni ( CN ) 2 - (2) PCl5 4 (3) BrF5 (4) PF5 JEE Main 2024 (30 Jan Shift 2) JEE Main Previous Year Paper
Q45. List - I List - II (Complex ion) (Spin only magnetic moment in B.M.) (A) [Cr(NH3)6]3+ (I) 4.90 Match List - I with List - II. Choose the (B) [NiCl4]2β (II) 3.87 (C) [CoF6]3β (III) 0.0 (D) [Ni(CN)4]2β (IV) 2.83 correct answer from the options given below : (1) (A)-(II), (B)-(III), (C)-(I), (D)-(IV) (2) (A)-(II), (B)-(IV), (C)-(I), (D)-(III) (3) (A)-(I), (B)-(IV), (C)-(II), (D)-(III) (4) (A)-(IV), (B)-(III), (C)-(I), (D)-(II)
Q45.Which among the following halide/s will not show SN1 reaction: (1) H2C = CH - CH2Cl (2) CH3 - CH = CH - Cl (3) (4)
Q45.An octahedral complex with the formula CoCl3 β nNH3 upon reaction with excess of AgNO3 solution gives 2 moles of AgCl. Consider the oxidation state of Co in the complex is ' x '. The value of " x + n " is ______ (1) 6 (2) 8 (3) 3 (4) 5
Q45. In the above reaction product ' P ' is JEE Main 2024 (09 Apr Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)
Q45.Identify the reagents used for the following conversion (1) A = LiAlH4, B = NaOH(aq), C = NH2 βNH2 / KOH ethylene glycol (2) A = LiAlH4, B = NaOH(alc) , C = Zn / HCl (3) A = DIBAL βH, B = NaOH(aq) C = NH2 βNH2 / KOH ethylene glycol (4) A = DIBAL βH, B = NaOH(alc), C = Zn / HCl
Q45.In chromyl chloride test for confirmation of Clβ ion, a yellow solution is obtained. Acidification of the solution and addition of amyl alcohol and 10% H2O2 turns organic layer blue indicating formation of chromium pentoxide. The oxidation state of chromium in that is (1) +6 (2) +5 (3) +10 (4) +3
Q45.Identify correct statements from below: A. The chromate ion is square planar. JEE Main 2024 (31 Jan Shift 1) JEE Main Previous Year Paper B. Dichromates are generally prepared from chromates. C. The green manganate ion is diamagnetic. D. Dark green coloured K2MnO4 disproportionates in a neutral or acidic medium to give permanganate. E. With increasing oxidation number of transition metal, ionic character of the oxides decreases. Choose the correct answer from the options given below: (1) B, C, D only (2) A, D, E only (3) A, B, C only (4) B, D, E only
Q45.Which one of the following complexes will exhibit the least paramagnetic behaviour? [Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27 ] (1) [Cr(H2O)6]2+ (2) [Fe(H2O)6]2+ (3) [Co(H2O)6]2+ (4) [Mn(H2O)6]2+
Q46.Yellow compound of lead chromate gets dissolved on treatment with hot NaOH solution. The product of lead formed is a : (1) Tetraanionic complex with coordination number (2) Neutral complex with coordination number four six (3) Dianionic complex with coordination number six (4) Dianionic complex with coordination number four
Q46.Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R . Assertion A : In aqueous solutions Cr2 + is reducing while Mn3 + is oxidising in nature. Reason R: Extra stability to half filled electronic configuration is observed than incompletely filled electronic configuration. In the light of the above statement, choose the most appropriate answer from the options given below: (1) Both A and R are true and π is the correct (2) Both A and R are true but R is not the correct explanation of A explanation of A (3) A is false but R is true (4) A is true but R is false
Q46.Given below are two statements : Statement I : Piciric acid is 2,4,6 - trinitrotoluene. Statement II : Phenol - 2,4 - disulphonic acid is treated with Conc. HNO3 to get picric acid. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Statement I is incorrect but Statement II is (2) Both Statement I and Statement II are incorrect correct (3) Statement I is correct but Statement II is (4) Both Statement I and Statement II are correct incorrect
Q46.The correct order of reactivity in electrophilic substitution reaction of the following compounds is: (1) B > C > A > D (2) D > C > B > A (3) A > B > C > D (4) B > A > C > D
Q46.If an iron (III) complex with the formula [Fe(NH3)x(CN)y]β has no electron in its eg orbital, then the value of x + y is JEE Main 2024 (04 Apr Shift 2) JEE Main Previous Year Paper (1) 4 (2) 5 (3) 6 (4) 3
Q46. The major products formed : A and B respectively are: JEE Main 2024 (06 Apr Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)
Q46.Identify the correct set of reagents or reaction conditions ' X ' and ' Y ' in the following set of transformation (1) X = dil.aq. NaOH, 20βC, Y = Br2/CHCl3 (2) X = conc.alc. NaOH, 80βC, Y = Br2/CHCl3 (3) X = dil.aq. NaOH, 20βC, Y = HBr /acetic (4) X = conc.alc. NaOH, 80βC, Y = HBr/ acetic acid acid
Q46.Which among the following compounds will undergo fastest SN2 reaction. (1) (2) (3) (4)
Q46.Which of the following reaction is correct? (1) (2) (3) (4) C2H5 CONH2 + Br2 + NaOH βC2H5 CH2 NH2 + Na2 CO3 + NaBr + H2O