Class 11 Chemistry — Chapter 2: Structure of Atom Online Test

1. For hydrogen atom, the ratio of radii of 1st and 3rd orbit is:

2. The number of radial nodes in 5d orbital is:

3. The ionization energy of hydrogen atom in the ground state is:

4. The electronic configuration of neon (Z=10) is:

5. The electronic configuration of helium (Z=2) is:

6. Why do electrons prefer to occupy different orbitals of equal energy before pairing?

7. When two subshells have the same value, the one that fills first is the one with:

8. Which d-orbitals have lobes oriented between the axes (at 45° angles)?

9. The radial probability distribution curve of a 2s orbital shows:

10. The value of is associated with:

11. The azimuthal quantum number primarily determines the:

12. If , how many orbitals are possible in that shell?

13. The three dumbbell-shaped orbitals oriented along x, y, and z axes are:

14. What physical meaning does the wave function itself have?

15. The first line of the Brackett series corresponds to which transition?

16. Which equation represents Einstein’s photoelectric effect?

17. What is the wavelength of a radio wave with frequency ?

18. Which of the following is a correct postulate of Bohr’s atomic model?

19. In Chadwick’s experiment, which element was bombarded with alpha particles to discover the neutron?

20. What conclusion did Rutherford draw from the gold foil experiment?

1. Which subatomic particle contributes to both the mass and stability of the nucleus but not to the atomic number?

2. The maximum number of electrons in a p-subshell is:

3. The number of orbitals present in the 3rd shell () is:

4. How does increasing gas pressure typically affect spectral lines (emission or absorption)?

5. Which of the following statements is correct?

6. The significance of quantum numbers is that they:

7. Bohr’s model could not explain the fine structure of hydrogen spectrum because:

8. Which observation cannot be explained by classical wave theory but is explained by Planck’s quantum theory?

9. The radial probability distribution curve of a 2s orbital shows:

10. If an electron is in shell, it is in which orbital?

11. In transition metal complexes, splitting of d-orbitals into and sets is due to:

12. Who first proposed the concept of atom as an indivisible particle?

13. Which subshell can have a maximum of 14 electrons?

14. Which limitation of Bohr’s model was later resolved by quantum mechanics?

15. Which spectral series of hydrogen lies in the ultraviolet region?

16. Which key limitation made the plum pudding model incompatible with atomic emission spectra?

17. Which hydrogen spectral series lies entirely in the visible region?

18. The orientation of an orbital in space is determined by:

19. Which scientist first demonstrated the wave nature of light through the double-slit experiment?

20. In an octahedral field, orbitals pointing directly along the axes experience:

21. Hund’s rule of maximum multiplicity states that:

22. What is the value of Planck’s constant ?

23. The first line of Paschen series corresponds to which transition?

24. Which of the following is correct about the principal quantum number?

25. Which hydrogen series falls in the infrared region?

26. Which region of the electromagnetic spectrum is responsible for heating effect in sunlight?

27. The frequency of visible light of wavelength 600 nm is approximately:

28. Which factor does not affect the kinetic energy of emitted photoelectrons?

29. What is the condition for allowed orbits in Bohr’s theory?

30. The probability distribution of a p-orbital is:

1. The term “quantum” of light refers to:

2. Why do elements like Cr, Mo, Cu, Ag show anomalous configurations?

3. How many orbitals are present in the p-subshell?

4. Which statement about electromagnetic waves is correct?

5. Which of the following statements is correct?

6. Which orbital has a spherical shape around the nucleus?

7. The splitting of white light into its component colors is called:

8. Which statement about orbitals is correct?

9. The electronic configuration of silver (Z=47) is anomalous and written as:

10. A stellar spectrum shows strong dark Na “D” lines near and . This most directly indicates:

11. If , how many orientations of orbitals are possible?

12. Hund’s rule is especially relevant for:

13. In Bohr’s orbit model, angular momentum of an electron is quantized as:

14. Which experiment first gave evidence of electron spin?

15. The probability distribution of a p-orbital is:

16. Which particle has no charge but nearly the same mass as a proton?

17. Which statement about Schrödinger’s wave equation is correct?

18. Why is copper (Z=29) an exception to the normal Aufbau filling?

19. The dark Fraunhofer lines observed in sunlight are an example of:

20. Heisenberg’s uncertainty principle is a direct consequence of:

21. In transition metal complexes, splitting of d-orbitals into and sets is due to:

22. What is the general shape of p-orbitals?

23. If the wave number of light is , its wavelength is:

24. If frequency of incident light equals threshold frequency, then:

25. Which formula did Bohr use to explain the hydrogen line spectrum?

26. Which of the following phenomena can be explained using the uncertainty principle?

27. Which orbital is spherical in shape and smallest in size?

28. What does the quantum number in Bohr’s model represent?

29. Which situation yields a bright-line emission spectrum?

30. Which of the following represents a stable noble gas configuration?

31. How many orbitals are present in the d-subshell?

32. In Bohr’s model, the energy difference between two orbits is given by:

33. The wave number () for the first line of Balmer series in hydrogen is:

34. The shape of an orbital is determined by which quantum number?

35. Planck introduced his quantum hypothesis to explain:

36. Before the discovery of neutrons, which problem remained unresolved in atomic models?

37. Which transition produces the shortest wavelength line in a hydrogen series?

38. Which subatomic particle is responsible for chemical bonding and reactivity?

39. The speed of electromagnetic waves in a medium is less than in vacuum because:

40. Why are half-filled and fully filled subshells more stable?

41. For hydrogen atom, the ratio of radii of 1st and 3rd orbit is:

42. Which graph best represents Einstein’s photoelectric equation?

43. Which of the following elements has the configuration [He] 2s² 2p²?

44. Which of the following statements about s-orbitals is correct?

45. Which of the following shows an anomalous configuration due to fully filled d-subshell?

46. The concept of standing electron waves inside the atom was used by:

47. The actual configuration of molybdenum (Z=42) is:

48. The electron density in an s-orbital is maximum at:

49. Which of the following orbital filling violates Hund’s rule?

50. Which property of light is explained by the phenomenon of interference?