Practice Questions

Q32.The number of following statement/s which is/are incorrect is ______ A) Line emission spectra are used to study the electronic structure B) The emission spectra of atoms in the gas phase show a continuous spread of wavelength from red to violet. C) An absorption spectrum is like the photographic negative of an emission spectrum D) The element helium was discovered in the sun by spectroscopic method

Q32.The pair from the following pairs having both compounds with net non-zero dipole moment is JEE Main 2023 (10 Apr Shift 1) JEE Main Previous Year Paper (1) 1, 4-Dichlorobenzene, 1, 3-Dichlorobenzene (2) cis-butene, trans-butene (3) CH2Cl2, CHCl3 (4) Benzene, anisidine

Q32.For OF2 molecule consider the following: (A) Number of lone pairs on oxygen is 2. (B) FOF angle is less than 104 . 5°. (C) Oxidation state of O is -2. (D) Molecule is bent 'V' shaped. (E) Molecular geometry is linear. Correct options are: (1) C, D, E only (2) B, E, A only (3) A, C, D only (4) A, B, D only

Q32.Which one of the following elements will remain as liquid inside pure boiling water? JEE Main 2023 (06 Apr Shift 2) JEE Main Previous Year Paper (1) Ga (2) Br (3) Li (4) Cs

Q32.Given below are two statements: Statement I: The decrease in first ionization enthalpy from B to Al is much larger than that from Al to Ga. Statement II: The d orbitals in Ga are completely filled. In the light of the above statements, choose the most appropriate answer from the options given below JEE Main 2023 (29 Jan Shift 2) JEE Main Previous Year Paper (1) Statement I is incorrect but statement II is (2) Both the statements I and II are correct correct. (3) Statement I is correct but statement II is incorrect (4) Both the statements I and II are incorrect

Q33.Match List I with List II List II List I (No. of lone pairs of e- (molecules/ions) on central atom) (A) IF7 I. Three (B) ICl4- II. One (C) XeF6 III. Two (D) XeF2 IV. Zero Choose the correct answer from the options given below: (1) A - II, B - III, C - IV, D - I (2) A - IV, B - III, C - II, D - I (3) A - II, B - I, C - IV, D - III (4) A - IV, B - I, C - II, D - III

Q33.Bond dissociation energy of E −H bond of the " H2E" hydrides of group 16 elements (given below), follows order. (A) O (B) S (C) Se (D) Te (1) A > B > C > D (2) A > B > D > C (3) B > A > C > D (4) D > C > B > A Q34. 1 mole of ideal gas is allowed to expand reversibly and adiabatically from a temperature of 27°C. The work done is 3 kJ mol−1 . The final temperature of the gas is _____ K (Nearest integer). Given Cv = 20 J mol−1 K−1

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.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.Strong reducing and oxidizing agents among the following , respectively, are (1) Ce3 + and Ce4 + (2) Ce4 + and Tb4 + (3) Ce4 + and Eu2 + (4) Eu2 + and Ce4 +

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.The compound which does not exist is (1) NaO2 (2) BeH2 (3) PbEt4 (4) NH42BeF4

Q33.Sum of π-bonds present in peroxodisulphuric acid and pyrosulphuric acid is

Q33.The number of molecules or ions from the following, which do not have odd number of electrons are _____ . (A) NO2 (B) ICl−4 (C) BrF3 (D) ClO2 (E) NO+2 (F) NO

Q33.Match List I with List II List I List II A. XeF4 I.See-saw B. SF4 II. Square planar JEE Main 2023 (31 Jan Shift 1) JEE Main Previous Year Paper C. NH4+ III. Bent T - shaped D.BrF3 IV. Tetrahedral Choose the correct answer from the options given below : (1) A - IV, B - III, C - II, D - I (2) A - II, B - I, C - III, D - IV (3) A - IV, B - I, C - II, D - III (4) A - II, B - I, C - IV, D - III

Q33.Which of the following statements are not correct? A. The electron gain enthalpy of F is more negative than that of Cl. B. Ionization enthalpy decreases in a group of periodic table. C. The electronegativity of an atom depends upon the atoms bonded to it. D. Al2 O3 and NO are examples of amphoteric oxides. Choose the most appropriate answer from the options given below: (1) A, B, C and D (2) A, B and D only (3) B and D only (4) A, C and D only

Q33.Which of the following statement(s) is/are correct? (A) The pH of 1 × 10–8 M HCl solution is 8. (B) The conjugate base of H2 PO4− is HPO2−4 . (C) Kw increases with increase in temperature. (D) When a solution of a weak monoprotic acid is titrated against a strong base at half neutralisation point, pH = 21 pKa . Choose the correct answer from the options given below: (1) (B), (C) (2) (A), (D) (3) (A), (B), (C) (4) (B), (C), (D)

Q33.The number of atomic orbitals from the following having 5 radial nodes is 7s, 7p, 6s, 8p, 8d

Q33.According to MO theory the bond orders for O22−CO, and NO+ respectively, are (1) 1, 3 and 3 (2) 1, 3 and 2 (3) 1, 2 and 3 (4) 2, 3 and 3

Q33.For compound having the formula GaAlCl4, the correct option from the following is (1) Ga is coordinated with CI in GaAlCl4 (2) Ga is more electronegative than AI and is present as a cationic part of the salt GaAlCl4 (3) CI forms bond with both AI and Ga in GaAlCl4 (4) Oxidation state of Ga in the salt GaAlCl4 is + 3

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.Choose the correct statement(s): A. Beryllium oxide is purely acidic in nature. B. Beryllium carbonate is kept in the atmosphere of CO2. C. Beryllium sulphate is readily soluble in water. D. Beryllium shows anomalous behavior. Choose the correct answer from the options given below: JEE Main 2023 (01 Feb Shift 1) JEE Main Previous Year Paper (1) A, B and C only (2) B,C and D only (3) A and B only (4) A only

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.The correct order of electronegativity for given elements is (1) P > Br > C > At (2) Br > P > At > C (3) Br > C > At > P (4) C > P > At > Br

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