Question
Chemistry Question on Classification
The order of increasing sizes of atomic radii among the elements O,S,Se and As is :
A
As<S<O<Se
B
Se<S<As<O
C
O<S<As<Se
D
O<S<Se<As
Answer
O<S<Se<As
Explanation
Solution
On moving down in a group atomic radii increases due to successive addition of extra shell hence
O<S<Se
Further As is in group 15 having one less electron in its p orbital hence have higher atomic radii than group 16 elements.
i.e.,O<S<Se<As