The d-and f-Block Elements Mock Test – Class 12 Chemistry

1. In the acidic reduction half-reaction

the values of and are respectively:

2. For one mole of permanganate, the order of decreasing oxidising capacity based on the number of electrons accepted is:

3. A graph shows the number of commonly accessible oxidation states on the vertical axis and increasing atomic number across the actinoid series on the horizontal axis. The most reasonable overall pattern is:

4. Assertion: The permanganate ion is intensely purple even though manganese is in a configuration.
Reason: Its strong colour is mainly associated with charge-transfer absorption rather than an ordinary - transition.

5. A graph of atomic radius against atomic number for the first transition series is expected to show:

6. A learner says, “Because actinoid compounds show greater covalency, every actinoid compound must be a neutral molecular substance.” The best evaluation is:

7. Which statement most accurately describes oxidation states in the actinoid series?

8. Potassium permanganate can act as a self-indicator in many acidic redox titrations because:

9. A student uses an -factor of for permanganate after being told that the reaction produces . The error is that the student:

10. A transition-metal solution absorbs mainly orange light. Its observed colour is expected to be closest to:

11. Assertion: and show closely similar chemical behaviour.
Reason: Their atomic and ionic radii are nearly equal as a consequence of lanthanoid contraction.

12. The generally high melting and boiling points of many transition metals are mainly associated with:

13. The following standard reduction potentials are supplied.

The strongest reducing metal among X, Y, and Z is:

14. A mixture contains only and . Chemical analysis shows that the mixture contains of copper. Using and , the amounts of and , respectively, are:

15. For a subshell, the azimuthal quantum number is ______.

16. Match each ion in Column I with its -electron classification in Column II.

The appropriate matching is:

17. Consider the following statements about configuration irregularities in later transition series.
Statement I: They may arise because the and subshells are close in energy.
Statement II: Every irregularity can be predicted by applying one universal half-filled-subshell rule.
Statement III: Supplied configuration data should be used when a later-series ground state is requested.
Statement IV: An configuration is possible for a -block atom.
The valid statements are:

18. A simple ion generally does not show an ordinary - absorption because:

19. Match each ion in Column I with its -electron configuration in Column II.

The appropriate matching is:

20. The observed ground-state configuration of copper is:

21. A bar graph represents moles of electrons accepted per mole of oxidant under four conditions:
Case P: acidified
Case Q: neutral-medium
Case R: strongly alkaline
Case S: acidified
Arrange the bar heights in decreasing order:

22. Complete conversion of of into chromate occurs according to

The amounts of consumed and formed are respectively:

23. Match each aqueous ion in Column I with its commonly observed colour in Column II.

The appropriate matching is:

24. Match each species in Column I with its configuration in Column II.

The appropriate matching is:

25. An atom has the supplied configuration . Given that xenon contains electrons, the atomic number and block classification of the atom are:

26. In the phrase “progressive filling of an inner subshell,” progressive filling means that:

27. and the manganese centre in are both . Their contrasting colours are best explained by the fact that:

28. For ions of the same transition element in comparable coordination environments, increasing the positive oxidation state generally causes the ionic radius to:

29. Assertion: A ion is strongly paramagnetic.
Reason: Its seven orbitals can each contain one unpaired electron according to Hund’s rule.

30. In the balanced preparation equation

the value of is:

31. The general outer electronic configuration used to describe -block elements is:

32. Compared with lanthanoid compounds in corresponding oxidation states, actinoid compounds generally show:

33. Absorption bands produced by - transitions in lanthanoid ions are commonly:

34. The following potentials are supplied.

A piece of iron placed separately in standard solutions of and will:

35. Consider the following statements about interstitial compounds.
Statement I: They are often harder than the parent metal.
Statement II: Many retain metallic conductivity.
Statement III: Their compositions must always correspond to exact small whole-number ratios.
Statement IV: Small atoms such as , , , and may occupy the interstitial sites.
The valid statements are:

36. A graph plots moles of electrons accepted against moles of permanganate reduced. Three straight lines through the origin represent acidic, neutral, and strongly alkaline media. The slopes of these lines should be:

37. Examine the comparison between lanthanoids and actinoids.

The consistent rows are:

38. The qualitative stability of half-filled and completely filled subshells is best interpreted by the statement:

39. Use the periodic-table arrangement described below: a left block is followed by a central block and then a right block, while two long rows are printed separately beneath the table. The most suitable identification is:

40. Using

and

the standard cell potential for

is:

41. The inner-transition series are associated primarily with progressive filling of the:

42. Consider the following statements about the position of the -block.
Statement I: Lanthanoids are associated with period .
Statement II: Actinoids are associated with period .
Statement III: Their separate display prevents the main periodic table from becoming excessively wide.
Statement IV: Their detached position means they do not belong to any period.
The valid statements are:

43. Study the configuration and group assignments.

The pair of rows that contains fully consistent information is:

44. A claim states, “The oxidation state of a transition-metal ion is always equal to the number of its remaining electrons.” The most suitable evaluation is:

45. A separation method repeatedly transfers lanthanoid ions between two environments in which their complex stabilities differ slightly. Repetition is useful because:

46. Assertion: An alloy may be harder than either of the pure metals used to form it.
Reason: Atoms of different sizes can distort the lattice and hinder the movement of layers or defects through the solid.

47. Suppose the nuclear charge increases across a transition series while the shielding effect of added electrons also becomes stronger. The most reasonable prediction is that atomic radius will:

48. Examine the following statements.
Statement I: Every transition element belongs to the -block.
Statement II: Every -block element must necessarily be a transition element.
Statement III: A common ion with a partially filled subshell can establish transition character even when the neutral atom has .
The valid statements are:

49. Cerium has the supplied neutral configuration . The configuration of is:

50. commonly behaves as an oxidising species in aqueous solution because it tends to: