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invention category A group or set of inventions that are classified together because of common characteristics. Invention groups that include Agricultural, Communications, Computing, Energy, Transportation and more.
Elements are organised into blocks by the orbital type in which the outer electrons are found. These blocks are named for the characteristic spectra they produce: sharp (s), principal (p), diffuse (d), and fundamental (f). Atomic number The number of protons in an atom. Electron configuration