Asked by pritam | 20th Feb, 2011, 05:20: PM

Expert Answer:

Dear student

Groups are vertical columns while periods are horizontal rows

Group 1,2 and 13 to 18 elements are called representative elements. In these elements the ultimate shell is incompletely filled

Group 3 to 12 are called transition elements

For your boards only learn first 20 elements

Please post ur querries separately

Answered by  | 20th Feb, 2011, 09:18: PM

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