Can anyone list me all the 8 groups of the periodic table , going in order of course?

Compare and contrast physical changes with chemical changes.

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

The excretory system, need answers for all: )