Most of the dissolved substance in sea water is: nitrogen hydrogen chloride sodium

Water (2510 g ) is heated until it just begins to boil. if the water absorbs 5.09×105 j of heat in the process, what was the initial temperature of the water?

What’s the percent by mass of carbon in c10h14n2

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?