What do atomic radius and ionic radius mean? Describe them.

(N/A) Atomic radius:
- $\rightarrow$ Atomic radius is defined as one-half of the distance between the nuclei of two covalently bonded atoms of the same element in a molecule.
- In the case of metals,the atomic radius is referred to as the metallic radius,which corresponds to one-half of the distance between two adjacent atoms in a metallic crystal lattice.
Ionic radius:
- $\rightarrow$ Ionic radius refers to the effective size of an ion (cation or anion).
- It represents the distance from the nucleus of the ion to the point where it exerts an influence in an ionic bond.
- The size of a cation is always smaller than its parent atom due to the loss of electrons and increased effective nuclear charge,whereas the size of an anion is always larger than its parent atom due to increased electron-electron repulsion.