Question

The elements in group 17 of the periodic table are all called halogens. All halogens have the same

0
atomic number.
atomic mass.
number of possible isotopes.
number of valence electrons.

Answer 1

number of valence electrons

Step-by-step explanation:

All of the elements in group 17, also known as group 7A, have 7 valence electrons.

No two elements have the same atomic number nor atomic mass in elemental form.

Halogens may have any number of isotopes.