N2O difference in electronegativity

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?

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.

In which block of the periodic table is uranium (u) found? s blockd blockp blockf block