26. Group 17 (VIIA) elements are __________.

27. Group 18 (VIIIA) elements are ______________.

28. The ‘4f’ elements are called ____________ or ____________ .

29. The 5f elements are called _____________ or as __________. They are from 90Th to 103Lr .

30. __________ or ___________ are elements which have properties that are intermediate between the properties of metals and non-metals.

31. All elements in s-block are ________, whereas in p-block (except 18th group) there are metals, non-metals and metalloids.

32. The distance between the nucleus and outer most shell is known as ___________.

33. Atomic radius is measured in __________ units. (1 pm = 10-12 m)

34. In general the positive ions are called _________ and negative charged ions are called anions.

35. The energy required removing an electron from the outer most orbits or shell of a neutral gaseous atom is called _____________.

36. The energy required removing the first electron from the outer most orbits or shell of a neutral gaseous atom of the element is called its _________________.

37. The energy required to remove an electron from uni- positive ion of the element is called the _______________ of that element and so on.

38. If the nuclear charge increases then ionization energy is ___________.

39. More the shells with electrons between the nucleus and the valence shell, they act as screens and decrease nuclear attraction over valence electron. This is called the ___________.

40. If more the screening effect, less is the _____________.

41. If more the ______________, less is the ionization energy.

42. Ionization energy is expressed in _______ (or) ev.

43. The _____________ of an element is defined as the energy liberated when an electron is added to its neutral gaseous atom.

44. Electron affinity of an element is also called electron gain ____________ of that element.

45. The ___________ of an element is defined as the relative tendency of its atom to attract electrons towards it when it is bonded to the atom of another element.

46. ________ proposed that the electro negativity of an element is the average value of its ionization energy and electron affinity.

47. Electro negativity =

48. The most electronegative element is ‘_____’ and the least electronegative stable element is ‘______’.

49. Metals generally show less __________ character.

50. Metals are ___________ elements.

51. __________ are generally more electronegative due to their smaller atomic radii.

52. Dobereiner grouped the elements into _________ and Newlands gave the law of Octaves.

53. Elements in the Modern Periodic table are arranged in _____ groups and _____ periods.

54. All the d- block elements (except Zn group) are known as ________________ and all the f-block elements (both Lanthanides, Actinides) are known as _______________.