The outermost electrons of an atom that are in the orbitals of highest principal quantum number of all electrons in the atom and don't fill that orbital completely. [Physics Chemistry; v100; 5715-20; 1986.] [Organic Chemistry; 2nd ed; 48-50; 1997.]
As scientists who evolve with technology we treat innovation as a way of life, a life we dedicate to improvement and advancement of Safety, Health and Environment.
