1. Modern periodic law is based on:

2. Who proposed the modern periodic table?

3. Total number of periods in modern periodic table:

4. Elements of group 2 are known as:

5. s-block elements consist of groups:

6. Noble gases belong to which block?

7. Effective nuclear charge (Z_eff) is:

8. Atomic radius generally ______ across a period.

9. Which has the largest atomic radius?

10. Cation size is ______ its parent atom.

11. Ionization energy is measured in:

12. First ionization energy is highest for:

13. Electron affinity generally ______ across a period.

14. Which has the highest electronegativity?

15. Metallic character ______ down a group.

16. IUPAC group number for halogens is:

17. Which element is a d-block element?

18. Shielding constant is denoted by:

19. Which factor increases effective nuclear charge?

20. Assertion (A): Atomic radius decreases across period.
Reason (R): Effective nuclear charge increases.

21. Ionic radius of O²⁻ is ______ than O atom.

22. Which has the smallest size?

23. Second ionization energy is always:

24. Which element has highest ionization energy?

25. Electron affinity of chlorine is ______ fluorine.

26. Electronegativity scale by Pauling is based on:

27. Most metallic element is:

28. p-block contains groups:

29. Which is an f-block element?

30. Assertion (A): Noble gases have very low reactivity.
Reason (R): They have stable electronic configuration.

31. Group 1 elements are stored in:

32. Which has maximum number of valence electrons?

33. Ionic radius trend in isoelectronic series:

34. IE₁ of N is greater than O due to:

35. Electron affinity is maximum for:

36. Mulliken scale relates electronegativity to:

37. Non-metallic character is highest at:

38. Which period contains only 8 elements?

39. Modern periodic table has ______ groups.

40. Which element belongs to period 3, group 16?

41. Shielding effect is due to:

42. In group, atomic radius increases because:

43. Which has the lowest ionization energy?

44. Electron affinity is zero for:

45. Which block contains inner transition elements?

46. Which group is called chalcogens?

47. Assertion (A): Noble gases have zero electron affinity.
Reason (R): They have stable octet.

48. The most electronegative element is:

49. Which metal is liquid at room temperature?

50. Overall periodic trend: Metallic character is highest at: