55: Where are the most reactive nonmetal elements found on the periodic table?
$ O O O O
at the top of group 17
at the bottom of group 17
at the top of group 18
at the bottom of group 18

6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.