Which of the following pairs of elements could possibly be found in the same group on the periodic table? A forms a 2+ ion; B is an alkaline earth metal. A is a noble gas; B forms a 1- ion. A has 3 va

Which of the following pairs of elements could possibly be found in the same group on the periodic table? A forms a 2+ ion; B is an alkaline earth metal. A is a noble gas; B forms a 1- ion. A has 3 valence electrons; B is a halogen. A forms a 2- ion; B has the atomic number 12.