Title CHXI02_STRUCTURE OF ATOM.pdf ✅

NEET PREPARATION CHXI02:STRUCTURE OF ATOM NEET PREPARATION Date: April 16, 2025 Dura on: 0:03:00 Total Marks: 180 INSTRUCTIONS INSTRUCTIONS CHEMISTRY 1. The correct set of four quantum numbers for out‐ ermost electron of potassium (Z = 19) is [Q307299] (a) 3, 1, 0, 1 2 (b) 4, 0, 0, 1 2 (c) 3, 0, 0, 1 2 (d) 4, 1, 0, 1 2 2. Assertion : Atom is electrically neutral. Reason : A neutral particle, neutron is present in the nu‐ cleus of atom. [Q307116] (a) Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion. (b) Both Assertion and Reason are correct but Reason is not the cor‐ rect explanation of the Assertion. (c) Assertion is correct but Reason is incorrect. (d) Assertion is incor‐ rect but Reason is correct. 3. The de-Broglie wavelength of a particle of mass 6.63 g moving with a velocity of 100 ms − 1 is: [Q307242] (a) 10 − 33m (b) 10 − 35m (c) 10 − 31m (d) 10 − 25m 4. What is the de Broglie wavelength associated with the hydrogen electron in its third orbit? [Q307240] (a) 9.96 × 10 − 10 cm (b) 9.96 × 10 − 8 cm (c) 9.96 × 104 cm (d) 9.96 × 108 cm 5. The ratio of E2 − E1 to E4 − E3 for He + ion is approximately equal to (where En is the energy of n th orbit) [Q307162] (a) 10 (b) 15 (c) 17 (d) 12 6. Assuming that a 25 watt bulb emits monochro‐ matic yellow light of wavelength 0.57 × 10 − 6m. The rate of emission of quanta per second will be [Q307419] (a) 5.89 × 10 15 sec − 1 (b) 7.28 × 10 17 sec − 1 (c) 5 × 10 10 sec − 1 (d) 7.18 × 10 19 sec − 1 7. Assertion : Hydrogen has one elecctron in its orbit but it produces several spectral lines. Reason : There are many excited energy levels available. [Q307564] (a) If both Assertion & Reason are true and rea‐ son is the correct expla‐ nation of the assertion. (b) If both Assertion & Reason are true but rea‐ son is not the correct explanation of the assertion. (c) If Assertion is true statement but Reason is false. (d) Assertion is false but reason is true. 8. Arrange the following orbitals in decreasing or‐ der of energy. A. n = 3, l = 0, m = 0 B. n = 4, l = 0, m = 0 C. n = 3, l = 1, m = 0 D. n = 3, l = 2, m = 1 [Q307317] (a) D > B > C > A (b) A > C > B > D (c) B > D > C > A (d) D > B > A > C ( ) ( ) 4/19/25, 4:14 PM CHXI02:STRUCTURE OF ATOM file:///C:/Users/DSREENATH/Downloads/NEET/CHEMISTRY/MEDIUM/QUESTIONS/CHXI02_STRUCTURE OF ATOM.html 1/5

NEET PREPARATION (a) The number of max‐ ima in radial probability distribution curve of 2s orbital are two (b) At the node, the value of the radial func‐ tion changes from posi‐ tive to negative (c) 3dZ 2 has 3 angular nodes (d) Both (1) and (2) 21. Which one is the wrong statement? [Q307613] (a) The uncertainty principle is ΔE × Δt ≥ h 4π . (b) Half filled and fully filled orbitals have greater stability due to greater exchange en‐ ergy, greater symmetry and more balanced arrangement. (c) The energy of 2s-or‐ bital is less than the en‐ ergy of 2p-orbital in case of hydrogen like atoms. (d) de-Broglie’s wave‐ length is given by λ = h mv , where m = mass of the particle, v = group velocity of the particle. 22. Ionisation energy of He + is 19.6 × 10 − 18 J/ atom. The energy of the first sta‐ tionary state (n = 1) of Li 2 + is [Q307155] (a) 4.41 × 10 − 16 J/ atom (b) −4.41 × 10 − 17 J/ atom (c) 2.2 × 10 − 15 J/ atom (d) 8.82 × 10 17 J/ atom 23. The uncertainties in the position of two parti‐ cles A and B are 2 nm and 4 nm, respectively. The ratio of uncertainties in the measurement of velocity if mass of B is 1.5 times higher than that of A is [Q307370] (a) 1 : 4 (b) 2 : 1 (c) 4 : 1 (d) 3 : 1 24. Which of the following options does not repre‐ sent ground state electronic configuration of an atom? [Q307273] (a) 1s 22s 22p 63s 23p 63d 84s 2 (b) 1s 22s 22p 63s 23p 63d 94s 2 (c) 1s 22s 22p 63s 23p 63d 104s 1 (d) 1s 22s 22p 63s 23p 63d 54s 1 25. If elements with principal quantum number, n > 4 is not allowed in nature, the number of possible elements would be [Q307467] (a) 60 (b) 32 (c) 64 (d) 50 26. The de Broglie wavelength of a tennis ball of mass 60 g moving with a velocity of 10 metres per second is approximately [Q307221] (a) 10 − 31 metres (b) 10 − 16 metres (c) 10 − 25 metres (d) 10 − 33 metres 27. Which of the following sets of quantum num‐ bers represents the 19th electron in chromium? (Z = 24 for Cr ) [Q307268] (a) 4, 0, 0, 1/2 (b) 4, 1, − 1, 1/2 (c) 3, 2, 2, 1/2 (d) 3, 2, − 2, 1/2 28. If n and l are the principal and azimuthal quan‐ tum numbers, then the expression for calculating the total number of electrons an energy level can accommodate is [Q307466] (a) l = n ∑ l = 1 2(2l + 1) (b) l = n − 1 ∑ l = 1 2(2l + 1) (c) l = n + 1 ∑ l = 0 2(2l + 1) (d) l = n − 1 ∑ l = 0 2(2l + 1) 29. Which are in the ascending order of wave‐ length? [Q307565] (a) H ( 3→2 ) , H ( 4→2 ) , H ( 5→2 ) , . . . . . lines in Balmer series of hydrogen atom (b) Lyman limit, Balmer limit, Paschen limit in the hydrogen spectrum (c) Blue, violet, yellow, red colours in solar spectrum (d) X-rays, Cosmic rays, γ − rays 30. Ejection of the photoelectron from metal in the photoelectric effect experiment can by stopped by applying 0.5 V when the radiation of 250 nm is used. The work function of the metal is: [Q307386] (a) 4 eV (b) 5.5 eV (c) 4.5 eV (d) 5 eV 31. How many d-electrons in Cu + (At.no.=29) can have the spin quantum number − 1 2 ? [Q307311] (a) 3 (b) 7 (c) 5 (d) 9 32. Each hydrogen atom is excited by giving 10.2eV. The maximum number of spectral lines in the emission is equal to [Q307572] (a) 1 (b) 2 ( ) 4/19/25, 4:14 PM CHXI02:STRUCTURE OF ATOM file:///C:/Users/DSREENATH/Downloads/NEET/CHEMISTRY/MEDIUM/QUESTIONS/CHXI02_STRUCTURE OF ATOM.html 3/5
NEET PREPARATION (c) 3 (d) 4 33. A light whose frequency is equal to 6 × 10 14Hz is incident on a metal whose work function is 2 eV (h = 6.63 × 10 − 34 Js, 1 eV = 1.6 × 10 − 19 J). The maximum energy of electrons emitted will be [Q307377] (a) 2.49 eV (b) 4.49 eV (c) 0.49 eV (d) 5.49 eV 34. The electron in the hydrogen atom undergoes transition from higher orbitals to lower orbital of radius 211.6 pm. This transition is associated with: [Q307567] (a) Lyman series (b) Balmer series (c) Paschen series (d) Brackett series 35. Electronic transition in Li 2 + ion takes from n2 to n1 shell when electrons transition to 1 st shell from 3 rd shell, the number of spectral line formed are [Q307566] (a) 10 (b) 8 (c) 5 (d) 3 36. The shape of the orbital with the value of 1 = 2 and m = 0 is [Q307452] (a) spherical (b) double dumbbell (c) trigonal planar (d) square planar 37. An isotone of 76 32Ge is (i) 77 32Ge (ii) 77 33As (iii) 77 34Se (iv) 78 34Se [Q307130] (a) Only (i) and (ii) (b) Only (ii) and (iii) (c) Only (ii) and (iv) (d) Only (ii), (iii) and (iv) 38. The energy of an electron in the first Bohr orbit of hydrogen atom is −2.18 × 10 − 18 J. Its energy in the third Bohr orbit is [Q307136] (a) 1 27 of this value (b) 1 9 of this value (c) three times of this value (d) one third of this value 39. The measurement of the electron position is as‐ sociated with an uncertainty in momentum, which is equal to 1 × 10 − 18 g cm s − 1 . The uncer‐ tainty in electron velocity is (mass of an electron is 9 × 10 − 28g) [Q307368] (a) 1 × 10 6cm s − 1 (b) 1 × 10 5cm s − 1 (c) 1 × 10 11cm s − 1 (d) 1.1 × 10 9cm s − 1 40. The energy of e − in first orbit of He + is −871.6 × 10 − 20 J. The energy of in first orbit of H is: [Q307150] (a) −871.6 × 10 − 20 J (b) −435.8 × 10 − 20 J (c) −217.9 × 10 − 20 J (d) −108.9 × 10 − 20 J 41. The work function of a metal is 4.2eV. If radia‐ tion of 2000 A falls on the metal, then the kinetic energy of the fastest photoelectron is [Q307383] (a) 1.6 × 10 − 19 J (b) 16 × 10 − 10 J (c) 3.2 × 10 − 19 J (d) 6.4 × 10 − 10 J 42. Which transition in the hydrogen atomic spec‐ trum will have the same wavelength as the Balmer transition (i.e. n = 4 to n = 2 ) of He + spectrum? [Q307575] (a) n = 4 to n = 3 (b) n = 3 to n = 2 (c) n = 4 to n = 2 (d) n = 2 to n = 1 43. If E1 , E2 andE3 represent respectively the ki‐ netic energies of an electron, an alpha particle and a proton each having same de Broglie wave‐ length then [Q307259] (a) E1 > E3 > E2 (b) E2 > E3 > E1 (c) E1 > E2 > E3 (d) E1 = E2 = E3 44. The ionisation energy of a hydrogen atom is 13.6 eV. The energy of the third-lowest elec‐ tronic level in doubly ionised lithium ion (Z = 3) is [Q307170] (a) −28.7 eV (b) −54.4 eV (c) −122.4 eV (d) −13.6 eV 45. Statement A : The radius of the first orbit of hydrogen atom is 0.529 o A Statement B : Radius of each circular orbit (rn )0.529 o A(n 2 /Z), where n = 1, 2, 3 and Z = atomic number [Q307208] (a) Statement A is cor‐ rect but statement B is incorrect (b) Statement A is in‐ correct but statement B is correct (c) Both statements are correct (d) Both statements are incorrect 4/19/25, 4:14 PM CHXI02:STRUCTURE OF ATOM file:///C:/Users/DSREENATH/Downloads/NEET/CHEMISTRY/MEDIUM/QUESTIONS/CHXI02_STRUCTURE OF ATOM.html 4/5