# The correct order of the atomic radii of

Question:

The correct order of the atomic radii of $\mathrm{C}, \mathrm{Cs}, \mathrm{Al}$, and $\mathrm{S}$ is :

1. $\mathrm{C}<\mathrm{S}<\mathrm{A} 1<\mathrm{Cs}$

2. $\mathrm{S}<\mathrm{C}<\mathrm{Cs}<\mathrm{Al}$

3. $\mathrm{S}<\mathrm{C}<\mathrm{Al}<\mathrm{Cs}$

4. $\mathrm{C}<\mathrm{S}<\mathrm{Cs}<\mathrm{Al}$

Correct Option:

Solution:

On going down the group, size increases while going from left to right in a period size decreases, so order is $\mathrm{C}<\mathrm{S}<\mathrm{Al}<\mathrm{Cs}$.