31. Donor impurity atoms have more valence electrons than the atoms they replace in the intrinsic semiconductor lattice. 32. The molecule ClO 2 has an odd number of valence electrons , and therefore, it is a radical. 33. For transition metal compounds, the 16 valence electrons ( eight from ligands, eight from the metal ). 34. As a result, a carbon atom forms four covalent bonds by sharing valence electrons with other atoms. 35. All chalcogens have six valence electrons . 36. This theory predicts that tetrametallic clusters with 60 valence electrons will adopt tetrahedral geometry with six M-M bonds. 37. Elements that contain the same number of valence electrons can be grouped together and display similar chemical properties. 38. All of the chalcogens have six valence electrons , leaving them two electrons short of a full outer shell. 39. Thus when determining the ordering of energy levels in general only the outer valence electrons must be considered. 40. This complex bonding behavior originates from the fact that boron has only three valence electrons ; this hinders polyhedra.
