Practice Questions
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Q33.For electron gain enthalpies of the elements denoted as ΔegH , the incorrect option is : (1) ΔegH(Cl) < ΔegH(F) (2) ΔegH(Se) < ΔegH(S) (3) ΔegH(I) < ΔegH(At) (4) ΔegH(Te) < ΔegH(Po) Q34. 0. 3 g of ethane undergoes combustion at 27°C in a bomb calorimeter. The temperature of calorimeter system (including the water) is found to rise by 0. 5°C . The heat evolved during combustion of ethane at constant pressure is kJmol−1 . (Nearest integer) [Given : The heat capacity of the calorimeter system is 20 kJ K−1, R = 8. 3 JK−1 mol−1 . Assume ideal gas behaviour. Assume ideal gas behaviour. Atomic mass of C and H are 12 and 1 g mol−1 respectively]
Q33.Order of Covalent bond; A. KF > KI; LiF > KF B. KF < KI; LiF > KF C. SnCl4 > SnCl2; CuCl > NaCl D. LiF > KF; CuCl > NaCl E. KF < KI; CuCl > NaCl (1) C, E Only (2) B, C Only (3) B, C, E Only (4) A, B Only
Q33.Values of work function (W0) for a few metals are given below Metal Li Na K Mg Cu Ag W0 eV 2. 42 2. 3 2. 25 3. 7 4. 8 4. 3 The number of metals which will show photoelectric effect when light of wavelength 400 nm falls on it is _____ Given: h = 6. 6 × 10–34 J s c = 3 × 108 ms–1 e = 1. 6 × 10–19 C
Q33.The number of correct statements from the following is ........... A. For 1s orbital, the probability density is maximum at the nucleus B. For 2s orbital, the probability density first increases to maximum and then decreases sharply to zero. C. Boundary surface diagrams of the orbitals encloses a region of 100% probability of finding the electron. D. p and d -orbitals have 1 and 2 angular nodes respectively E. probability density of p -orbital is zero at the nucleus
Q33.Given below are two statements : Statement I : SO2 and H2O both possess V-shaped structure Statement II : The bond angle of SO2 is less than that of H2O. 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 correct(4) Statement I is correct but Statement II is incorrect
Q33.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : The energy required to form Mg2 + from Mg is much higher than that required to produce Mg+ Reason R:Mg2 + is small ion and carry more charge than Mg+ In the light of the above statements, choose the correct answer from the options given below. (1) Both A and R are true but R is NOT the correct (2) A is true but R is false explanation of A (3) A is false but R is true (4) Both A and R are true and R is the correct explanation of A
Q34.The enthalpy change for the adsorption process and micelle formation respectively are (1) ΔHads > 0 and ΔHmic < 0 (2) ΔHads > 0 and ΔHmic > 0 (3) ΔHads < 0 and ΔHmic > 0 (4) ΔHads < 0 and ΔHmic < 0
Q34.The density of a monobasic strong acid (Molar mass 24. 2 g mol) is 1. 21 kg L . The volume of its solution required for the complete neutralization of 25 mL of 0. 24 M NaOH is 10−2 mL (Nearest integer) Q35.' 25 volume' hydrogen peroxide means (1) 1 L marketed solution contains 250 g of H2O2 . (2) 1 L marketed solution contains 75 g of H2O2 . (3) 100 mL marketed solution contains 25 g of (4) 1 L marketed solution contains 25 g of H2O2 . H2O2 .
Q34.H2O2 acts as a reducing agent in (1) 2NaOCl + H2O2 →2NaCl + H2O + O2 (2) 2Fe2 + + 2H+ + H2O2 →2Fe3 + + 2H2O (3) Mn2 + + 2H2O2 →MnO2 + 2H2O (4) Na2 S + 4H2O2 →Na2SO4 + 4H2O
Q34.The number of statement's, which are correct with respect to the compression of carbon dioxide from point (a) in the Andrews isotherm from the following is _________. JEE Main 2023 (24 Jan Shift 2) JEE Main Previous Year Paper A. Carbon dioxide remains as a gas upto point (b) B. Liquid carbon dioxide appears at point (c) C. Liquid and gaseous carbon dioxide coexist between points (b) and (c) D. As the volume decreases from (b) to (c), the amount of liquid decreases
Q34.The bond order and magnetic property of acetylide ion are same as that of (1) O2+ (2) N2+ (3) NO+ (4) O2−
Q34.What happens when methane undergoes combustion in systems A and B respectively? (1) System A System B (2) System A System B Temperature rises Temperature remainsTemperaturesame remains same Temperature rises (3) System A System B (4) System A System B Temperature falls Temperature remainsTemperaturesame falls Temperature rises
Q34.Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Loss of electron from hydrogen atom results in nucleus of ~1 . 5 × 10 – 3 pm size. Reason R: Proton H+ always exists in combined form. In the light of the above statements, choose the most appropriate answer from the options given below: (1) Both A and R are correct and R is the correct (2) A is correct but R is not correct explanation of A (3) A is not correct but R is correct (4) Both A and R are correct but R is NOT the correct explanation of A
Q34.Which one of the following pairs is an example of polar molecular solids? (1) SO2( s), CO2( s) (2) SO2( s), NH3( s) (3) MgO(s), SO2(s) (4) HCl(s), AlN(s)
Q34.For 1 mol of gas, the plot of pV vs p is shown below. p is the pressure and V is the volume of the gas. JEE Main 2023 (29 Jan Shift 1) JEE Main Previous Year Paper What is the value of compressibility factor at point A ? (1) 1 − RTVa (2) 1 + Vb (3) 1 −bV (4) 1 + RTVa
Q34.Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The first ionization enthalpy of 3d series elements is more than that of group 2 metals Reason (R): In 3d series of elements successive filling of d-orbitals takes place. In the light of the above statements, choose the correct answer from the options given below: (1) Both (A) and (R) are true and (R) is the correct (2) (A) is true but (R) is false explanation of (A) (3) (A) is false but (R) is true (4) Both (A) and (R) are true but (R) is not the correct explanation of (A)
Q34.In which of the following processes, the bond order increases and paramagnetic character changes to diamagnetic one? (1) O2 →O+2 (2) O2 →O2−2 (3) NO →NO+ (4) N2 →N+2 JEE Main 2023 (13 Apr Shift 1) JEE Main Previous Year Paper
Q34.For elements B, C, N Li, Be, O and F, the correct order of first ionisation enthalpy is (1) Li < Be < B < C < O < N < F (2) B < Li < Be < C < N < O < F (3) Li < Be < B < C < N < O < F (4) Li < B < Be < C < O < N < F
Q34.The number of species having a square planar shape from the following is XeF4, SF4, SiF4, BF4−, BrF4−, [Cu (NH3)4]2+, [FeCl4]2−, [PtCl4]2−
Q35.The number of following factors which affect the percent covalent character of the ionic bond is______ A) Polarising power of cation B) Extent of distortion of anion C) Polarisability of the anion D) Polarising power of anion
Q35.Match items of column I and II Column I (Mixture of compounds) Column II (Separation Technique) A. H2O / CH2Cl2 i. Crystallization ii. Differential solvent extraction B. C. Kerosene/Naphthalene iii. Column chromatography D. C6H12O6 / NaCl iv. Fractional Distillation (1) A - ( iii ) , B - ( iv ) , C - ( ii ) , D - ( i ) (2) A - ( ii ) , B - ( iii ) , C - ( iv ) , D - ( i ) (3) A - ( i ) , B - ( iii ) , C - ( ii ) , D - ( iv ) (4) A - ( ii ) , B - ( iv ) , C - ( i ) , D - ( iii )
Q35.Given (A) 2COg + O2g →2CO2g ΔH1o = - x kJ mol-1 (B) Cgraphite + O2g →CO2g ΔH2o = - y kJ mol-1 1 The ∆Ho for the reaction Cgraphite + 2O2g →COg is (1) 2x - y (2) x + 2y 2 2 x - 2y (3) (4) 2y - x 2
Q35.Reaction of BeO with ammonia and hydrogen fluoride gives 'A' which on thermal decomposition gives BeF2 and NH4F. What is 'A' ? (1) H3NBeF3 (2) NH42BeF4 (3) NH4BeF3 (4) NH42Be2F6
Q35.Given below are two statements: Statement I: SbCl5 is more covalent than SbCl3 Statement II: The higher oxides of halogens also tend to be more stable than the lower ones. 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 correct (2) Both Statement I and Statement II are incorrect (3) Both Statement I and Statement II are correct (4) Statement I is correct but statement II is incorrect
Q35.At 298 K N2(g) + 3H2(g) ⇌2 NH3(g), K1 = 4 × 105 N2(g) + O2(g) ⇌2 NO(g), K2 = 1. 6 × 1012 H2(g) + 12 O2(g) ⇌H2O(g), K3 = 1. 0 × 10−13 Based on above equilibria, the equilibrium constant of the reaction, 2 NH3(g) + 25 O2( g) ⇌2 NO(g) + 3H2O(g) is _____ ×10−33 (Nearest integer)