Which of the two will be chemically more reactive , element x with atomic number 17 or element y with atomic number 16?

Explanation

The electronic configuration of the two elements are as follows:
X(Z=16):K(2),L(8),M(6),Y(Z=17):K(2),L(8),M(7)`
the elemetn X needs two electrons to achieve this .This menas that the elemetn Y has a greater utge or desire to take up one elctron form an outside tom .It is therefore more reactive than the element X which needs two electrons