Which element has the largest atomic radius

Atomic radius is the distance from the nucleus to the last valance electron up to which the effect nucleus can be felt. The size of the atom depends on the Electrostatic interaction between nucleus and electron. Number of atomic orbitals present. With the increase in numbers of orbitals down the group the size of the atom increases. Again, as the numbers of electrons increases in the period ,the electrostatic interaction between nucleus and electron increases along the period. Therefore, size of atoms decreases along the period.

As expected the element with highest atomic radius is the last element of group 1 , Which is FRANCIUM ( Fr)

as

Explanation:

cc

answer; i believe that the correct answer is (a) potassium(k)