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

1. A claim says, “Valency and number of valence electrons are always identical.” The best evaluation is that the claim is

2. A classification method has four features: it keeps similar elements together, leaves spaces for unknown elements, predicts properties from neighbouring elements, and can revise doubtful atomic masses. This set of features most closely describes

3. In Newlands' arrangement, the word octave was used because the pattern was compared with

4. An element has first electron gain enthalpy , while element has . The stronger tendency to accept an electron is shown by

5. A proposed triad has end elements with atomic masses and . If it follows Dobereiner's rule, the middle atomic mass should be nearest to

6. A major limitation of Mendeleev's periodic table was that some element pairs had to be placed against increasing atomic mass to preserve chemical similarity. This showed that

7. A representative element has the valence-shell configuration . Its position is best described as

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

9. Oxidation state is best understood as

10. A neutral atom ends with . Its period, block-side family position, and group are best described as

11. The general electronic configuration often used for -block elements is

12. The oxide formula , with oxygen as , indicates that the oxidation state of is

13. The anomalous behaviour of many second-period elements compared with heavier members of their groups is mainly due to their

14. Match the terms in Column I with their correct meanings in Column II.

15. A student argues that and should both be acidic because both contain oxygen. The best correction is that

16. A halogen displacement record says that can oxidize to , but cannot oxidize to . This record supports the conclusion that

17. The table gives four atoms with qualitative size and attraction clues.

The atom expected to have the greatest electronegativity is

18. A final comparison says: “Across a period, atoms generally become smaller, ionization enthalpy and electronegativity increase, metallic character decreases, and oxide character changes from basic toward acidic.” The statement is

19. A family has the general valence-shell configuration , except for the first-period member with . The family is best identified as

20. The row with the most suitable -block family identification is

21. The increasing acidic character of oxides across a period is most closely related to

22. For a representative element with outer configuration , the most suitable group placement is

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

24. The strongest summary of electronegativity trends is that electronegativity

25. A bond between and is polar, and is more electronegative than . The best representation of the partial charges is

26. In an isoelectronic series, ionic radius decreases as nuclear charge increases. For , , , and , the largest ion is

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

28. A group element forms a simple hydride in which hydrogen behaves as . The expected formula is

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

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

31. The modern IUPAC group numbering system labels the vertical columns of the periodic table as

32. A record of period lengths is given below.

The row that needs correction is

33. The change from Mendeleev's basis to the modern basis can be summarized as a change from

34. Arrange the species , , , , and in increasing ionic radius.

35. Moving from left to right across a typical period, the broad change in element character is usually

36. Valency is best described as the

37. Non-metals are mainly located in the periodic table toward the

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

39. The best combined statement about electron gain enthalpy is that it

40. The oxidation state of phosphorus in , taking chlorine as , is

41. The limitation “atomic mass is not the fundamental basis” became clear from all of the following except

42. Down a group, first ionization enthalpy generally decreases because

43. A molecule has a bond between and . Chlorine is more electronegative than hydrogen. The bond polarity is best described as

44. The two series usually shown separately below the main body of the periodic table are

45. The -block is usually displayed below the main body of the periodic table because

46. Match the predicted names in Column I with the elements later associated with them.

47. The electron gain enthalpy comparison more negative than is best explained in the same way as

48. The name eka-aluminium was used by Mendeleev for an element predicted to lie below aluminium. The prefix eka indicated

49. A claim says, “All -block elements form only one fixed oxidation state because their group is fixed.” The best evaluation is that the claim is

50. Assertion: Metallic character generally increases down group .
Reason: Down the group, added shells and shielding make the outer electrons easier to remove.