The Prefix is Otterbox's least expensive iPhone case. The durable silicone, polycarbonate skeleton build of the OtterBox Prefix is thicker than the Commuter and Reflex, but also the least protective. The Prefix is a one-piece case, meaning that it does not snap in place like the Reflex .
carbon is considered tetravalent because it has four valence electrons the valence electrons are in the outermost shell of the atom and allows carbon to form four bonds to other atoms
Electron configuration is the key to an atomâs characteristics. Electron configuration determines the kinds and number of bonds an atom will form with other. atoms. With four valence electrons, carbon can form four covalent bonds with a variety of atoms. This ability makes large, complex molecules possible. In molecules with multiple carbons, each carbon bonded to four other atoms has a tetrahedral. shape. However, when two carbon atoms are joined by a double bond, the atoms joined to the carbons. are in the same plane as the carbons.