Question

While looking at bromine (Br) on the periodic table, a student needs to find another element with very similar chemical properties but with a different atomic mass. Which best describes the student’s options?

There are two possible elements, and they are directly to the left and right of bromine.
There are two possible elements, and they are directly above and below bromine.
There are many possible elements, and they are all in the same vertical column as bromine.

Answer 1

There are many possible elements, and they are all in the same vertical column as bromine.

Reason: elements in the same group (column) have the same number of valence electrons and therefore very similar chemical behavior. For Br (a halogen) other halogens such as F, Cl, I, At (and Ts) fit that description and each has a different atomic mass.