The ionic radii of $O^{2-}, F^{-}, Na^{+}$,and $Mg^{2+}$ are in the order :

Assertion $(A)$: The ionic radii of $Na^{+}$ and $F^{-}$ are same.
Reason $(R)$: Both $Na^{+}$ and $F^{-}$ are isoelectronic species.
The correct answer is:

Which of the following represents the correct order of atomic radius?

The order of magnitude of ionic radii of ions $Na^{+}$,$Mg^{2+}$,$Al^{3+}$ and $Si^{4+}$ is

Given two statements below :
Statement $I:$ In $Cl_2$ molecule the covalent radius is double of the atomic radius of chlorine.
Statement $II:$ Radius of anionic species is always greater than their parent atomic radius.
Choose the most appropriate answer from options given below :

The decreasing order of size of the isoelectronic series $K^{+}$,$Ca^{2+}$,$Cl^{-}$,and $S^{2-}$ is: