Which element has the largest atomic radius?
as
n
p
sb

The correct answer is Sb.

Explanation:

The atomic radius increases in the periodical table as the period of the element increases and as its group decreases. As all the elements belong to the same group (15), we must evaluate the one that has more electrons, comparing its atomic number because as the number of electrons of an element grows, it grows its atomic radius. In this case, the one that has more electrons, and therefore more atomic radius is the Sb.

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