What is the density of Sulfur Trioxide at 1.00 atm and 273 K?

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a

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.