An element in this group is attached to the alpha carbon of a carboxylic acid in the Hell-Volhard-Zelinsky (10[2])reaction. In mass spec, two peaks of equal height two units apart characterize a member of this group. An atom of a member of this group is displaced in a positive silver nitrate test. Adding magnesium (10[1])to hydrocarbons containing a member of this group creates Grignard (10[1])(“grin-yard”) reagents. (10[1])These elements, (-5[1])which are denoted with an X in organic (10[1])structures, can replace hydrogen since they both require one more electron for a full outer shell. (10[1]-5[1])For 10 points, name this group of elements with seven valence electrons, including fluorine and chlorine. (10[1]0[1])■END■