Q15 of 24 Page 5

Write the number of periods and groups in the Modern Periodic Table. How does the metallic character of elements vary on moving (i) from left to right in a period, and (ii) down a group? Give a reason to justify your answer. (CBSE 2010, 2007)

There are 7 periods and 18 groups in the modern periodic table.

Metallic character decreases from left to right across a period because as atomic size goes on decreasing so tendency to lose electrons decreases.
But down a group metallic character increases as atomic size increases and tendency to lose electrons increases.

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