Antimony has 2 naturally occurring isotopes. the mass of antimony-121 is 120.904 amu and the mass of antimony-123 is 122.904 amu. using the average atomic mass from the periodic table, find the abundance of each isotope. (remember that the sum of the two abundances must be 100. show your work.)

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?

Anthracite is so hard and pure it is also referred to as a renewable resource metamorphic rock hot bituminous coal dirty fuel

A5.00 g of a in . g of at aa 5.00 g of b in . g of .?at .