Structure of Atom Mock Test – Class 11 Chemistry

1. A metal surface is illuminated first with low-intensity radiation of frequency , and then with high-intensity radiation of frequency . The correct conclusion is

2. Cathode rays were found to have the same properties even when the gas in the tube and the cathode material were changed. This observation supports the idea that electrons are

3. The number of radial nodes in a orbital is given by . For , the number of radial nodes is

4. Match the value of in Column I with the subshell symbol in Column II.

5. For hydrogen, the energy of the level is

6. The electronic configuration represents

7. A configuration is not acceptable because

8. Assertion: A metal with a larger work function has a higher threshold frequency.
Reason: The threshold relation is , where is constant.

9. A sample contains of isotope , of isotope , and of isotope . Taking isotopic masses as , , and , the average atomic mass is

10. A hydrogen atom and are compared in the same Bohr level . Using , the radius of the orbit is

11. A pair of atoms has values and , while their neutron numbers are both . The pair is classified as

12. A wave has wavelength in vacuum. Taking , its frequency is

13. The pair and is not a pair of isobars because

14. Assertion: In the photoelectric effect, no electrons are emitted if the incident frequency is below threshold frequency.
Reason: Below threshold frequency, the energy of each photon is less than the work function of the metal.

15. Chadwick's experiment is most closely connected with the discovery of the

16. The term "orbital" in the quantum mechanical model means

17. The energy of a hydrogen electron changes from to . The transition is

18. Study the isotope data below.

The average atomic mass is

19. The most suitable experimental setup for Rutherford-type scattering is

20. Hund's rule is most directly used when electrons are being placed in

21. A radiation has wavelength . It falls on two metal surfaces with threshold wavelengths and , respectively. The correct conclusion is

22. The Thomson model could explain the neutrality of an atom because it proposed

23. A set of four quantum numbers is proposed for the last electron in a subshell: . The set is

24. The shell names , , , and correspond respectively to

25. A table lists four electromagnetic radiations.

The rows consistent with are

26. A photoelectric experiment gives the following records.

The row that contradicts the threshold-frequency condition is

27. Copper has the ground-state configuration instead of . The main reason is the stability of

28. Four species are listed below.

The species with protons and electrons is

29. A neutral atom has the configuration . The total number of electrons in orbitals with is

30. A cathode-ray tube experiment is repeated with neon gas, then with hydrogen gas, and finally with a different cathode metal. The same kind of negatively charged ray is obtained each time. The conclusion most directly supported is

31. The main reason for studying the structure of the atom is that it helps explain

32. The Paschen series limit of hydrogen is obtained when and . Its limiting wave number is

33. A learner says, "All orbitals in the same shell have the same number of angular nodes because they have the same ." The best correction is that angular nodes depend on

34. A record from a scattering experiment says:

The main purpose of this arrangement is to infer

35. A lamp emits of energy as photons of wavelength . Taking , , and , the number of photons emitted is closest to

36. Isobars are atoms that have

37. A particle has a very small mass but carries one unit of negative charge. Compared with a heavier particle carrying the same magnitude of charge, it should have

38. A ray in a discharge tube travels from the cathode, forms a shadow, rotates a light paddle wheel, and bends toward a positive plate. The most complete interpretation is that the ray

39. Average atomic mass of an element is calculated as a weighted average because naturally occurring samples may contain

40. Mass number of an atom is the total number of

41. The configuration corresponds to a neutral atom whose outermost shell contains

42. A sample of chlorine contains and . Taking the isotopic masses as and , the average atomic mass is

43. Assertion: Rutherford's model could not explain the stability of atoms.
Reason: A revolving electron should continuously lose energy according to classical theory.

44. A configuration is proposed as . The reason it is impossible is that

45. The maximum number of electrons in a subshell is

46. A neutral atom has the configuration . The number of valence electrons in this atom is

47. The orbital diagram for should have

48. De Broglie's hypothesis assigned wave character to

49. Two hydrogen orbits have principal quantum numbers and . The ratio is

50. A neutral atom has the configuration . It forms a ion. The configuration of the ion and the number of unpaired -electrons are respectively