State Modern Periodic Law. Discuss the periodic trends of atomic radii for elements of Group 1 to 2 and Group 13 to 17. [1+2]
WBBSE
Class X
Physical Science
Periodic Table
03 Mark
2025
Modern Periodic Law
The physical and chemical properties of elements are periodic functions of their atomic numbers.
Periodic Trend of Atomic Radius
- Across a period (Group 1 → Group 2 and Group 13 → Group 17), the atomic radius decreases from left to right.
- This is because the nuclear charge increases, pulling the electrons closer to the nucleus while the number of electron shells remains the same.
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