How many grams are in it

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?

How many oxygen atoms are there in 3.15 moles of hcl manganese (iv) oxide, mno2

Salt in oceans comes from and of rocks