By the way what do those symbols for the elements have in common (for number 7-11): Pb, Au, Cu, Hg, Na ? *

Why is permeable soil best for plants that need a lot of drainage?

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?

What is a possible quantum number set for an electron in the 3s orbital of a magnesium atom