How many grams of HgBr2 are present if you have 8.52x10^19 molecules of HgBr2

i do not get it   at all

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.

the answer is c.the valence of the atoms combine .