Atomic Radius Within a Group

The physical properties of the elements, such as melting point, boiling point and density are related to the atomic radius of the elements. Also, the atomic radius directly affects the ability of an atom to gain and lose electrons. The atomic radius is practically defined by assuming the shape of the atom as a sphere. The atomic radius is the distance between the nucleus and the outermost electron. But it is impossible to measure the atomic radius by separating the atoms from each other. Atomic Radius within a Group 

The atomic radius of a metal is equal to half the distance (rj between the nuclei of the neighbouring metal atoms. 

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