Question

exam 2: periodicity & electron configuration/em spectrum
a family of elements that has seven valence electrons is the
group 17
group 7
group 5
group 2

Explanation:

In the periodic table, elements in Group 17 (also known as the halogens) have seven valence electrons. Group 7 in the older numbering of transition - metal groups does not have seven valence electrons for all its elements. Group 5 elements have five valence electrons and Group 2 elements have two valence electrons.

Answer:

A. Group 17