Classification of Elements and Periodicity in Properties Mock Test – Class 11 Chemistry

1. Down a group, electronegativity generally decreases because

2. Consider the statements about hydrides and oxides as periodic indicators.
I. Hydride formulae can reflect valency patterns.
II. Oxide formulae can help infer oxidation state.
III. Similar oxide and hydride formulae were useful in Mendeleev's grouping.
IV. Hydride formulae always prove that two elements are isotopes.
The supported statements are

3. Arrange the halogens , , , and in decreasing electronegativity.

4. The table gives valence-shell configurations for some representative elements.

The row that needs correction is

5. Across period , the character of oxides generally changes from

6. The basic character of alkali metal hydroxides generally increases down the group. This trend is most closely related to

7. Metalloids are commonly found along the zig-zag boundary between metals and non-metals. A suitable example set is

8. In Mendeleev-style classification, oxide and hydride formulae were useful because they gave evidence about

9. The table gives qualitative data for halogens.

The row-wise trend is best explained by

10. The passage below describes two elements.

The shared chemical tendency is best explained by

11. Group elements commonly show oxidation state because their valence-shell configuration is generally

12. Assertion: Potassium is generally more reactive than sodium.
Reason: Potassium has a larger atomic size and lower first ionization enthalpy than sodium.

13. Assertion: First ionization enthalpy generally decreases from to .
Reason: Down group , the valence electron enters shells farther from the nucleus and experiences greater shielding.

14. A third-period representative element has outer configuration . Its valence electrons and simple valency are respectively

15. The strongest summary of electronegativity trends is that electronegativity

16. The process representing first ionization enthalpy is

17. Match the factor in Column I with its effect on first electron gain enthalpy in Column II.

18. An element has the electronic distribution . For a representative element, the number of valence electrons is

19. has greater first ionization enthalpy than because

20. A group element forms a simple hydride with hydrogen as . The formula that satisfies charge balance is

21. The third period has elements even though the shell has , , and subshells. The main reason is that

22. A configuration ends in . Without identifying the element by name, its period can be determined as

23. The anomalous order - in Mendeleev's table is best understood as a case where

24. The second electron gain enthalpy for an atom is usually positive because the second electron is added to

25. Match the series or region in Column I with its usual description in Column II.

26. A neutral element has , and another neutral element has . Their electronic distributions are and , respectively. The modern periodic-table reason for their similarity is

27. The vertical set containing elements such as , , and is best described as a

28. A periodic table based only on atomic mass faces a problem when two elements must be ordered as , then , even though has slightly greater atomic mass. The chemical reason for keeping this order is that

29. A table contains four statements about Mendeleev's merits. Identify the statement that does not represent a merit.

30. A periodic-property graph has radius maxima at group positions and ionization-enthalpy maxima near group positions. The two maxima appear in different places because

31. A statement says, “Because fluorine is the most electronegative element, it should show positive oxidation states with oxygen.” The best correction is that fluorine

32. Match the representative group with the simple valency idea.

33. Consider the statements about metals, non-metals, and metalloids in the periodic table.
I. Metals occupy much of the left and central part of the table.
II. Non-metals are concentrated mainly toward the upper right.
III. Metalloids commonly lie along a zig-zag boundary.
IV. All elements in the -block are metals.
The supported statements are

34. Same-shell electrons shield one another poorly compared with inner-shell electrons. This fact helps explain why, across a period,

35. When a period element forms strong multiple bonds with another small atom, while its heavier group member forms weaker multiple bonds less readily, the difference is mainly due to

36. Use the short passage below.

The most suitable inference is that is likely a

37. Across a period, the bonding tendency of simple compounds often changes from ionic character on the left toward covalent character on the right because

38. A representative element forms a simple hydride . If hydrogen is treated as monovalent, the simplest valency of in this hydride is

39. The row that best distinguishes a periodic pattern from a non-periodic listing is

40. A halogen in a simple metal halide such as usually has oxidation state

41. Consider the statements about first ionization enthalpy.
I. It generally increases across a period.
II. It generally decreases down a group.
III. It is the energy released when an electron is added to a gaseous atom.
IV. It is affected by atomic size, , and electronic configuration.
The supported statements are

42. Read the short classification case.

The strongest classification inference is that and probably

43. Moseley's work helped establish atomic number as the basis of classification by showing a connection between X-ray spectra and

44. A compact family-description card says: “Group elements generally form ions; group elements commonly form ions.” The difference is mainly due to

45. In the compound , oxygen has oxidation state . The oxidation state of carbon is

46. An element lies to the right of silicon in period and forms a covalent oxide that reacts with water to form an acid. This observation supports the idea that

47. A temporary systematic name begins with roots corresponding to the digits , , and . Using the roots and , the root sequence is

48. Consider the statements about -block elements.
I. They include groups to .
II. Their valence-shell configuration generally changes from to .
III. They are all highly electropositive metals.
IV. They include halogens and noble gases.
The supported statements are

49. Consider the statements about electronegativity.
I. It is the tendency of a bonded atom to attract the shared electron pair.
II. It is dimensionless on the Pauling scale.
III. It generally increases down a group.
IV. It can help predict bond polarity.
The supported statements are

50. Consider the statements about period number and shell filling.
I. The period number equals the highest occupied principal shell .
II. The third period contains elements because the subshell exists.
III. The second and third periods each contain elements.
IV. The fourth and fifth periods each contain elements.
The supported statements are