A single carbon atom can form a maximum of four covalent bonds. The number of covalent bonds that an atom can form is limited by its number of valence electrons. Carbon has four valence electrons, and it can use each of these four electrons for bonding.
The formation of four covalent bonds does not necessarily mean that carbon must bond with four atoms. It can form two double bonds, as in CO2; it could form a triple bond and a single bond, as in C2H2; or it could form a double bond and two single bonds, as in CH2O (formaldehyde).Learn More
The chemical elements most likely to form covalent bonds are those that share electrons, such as carbon, as opposed to those that take them from another element to form an ionic bond. In general, they are nonmetals with similar electronegativities. They are located toward the center of the periodic table, according to HowStuffWorks.Full Answer >
Atoms that typically form covalent bonds with each other have similar electronegativity, which expresses the atom's tendency to attract electrons, such as with carbon and hydrogen, which form methane. They stand in contrast to ionic bonds, where electronegativities are vastly different, as with sodium and chlorine, which combine to form table salt. These actually exist on a continuum with significant but lesser differences in electronegativity causing the formation of polar molecules.Full Answer >
A chlorine atom can form a single covalent bond, according to the University of Wisconsin chemistry department website. Chlorine atoms have seven electrons in their outer shells and can only share a single electron with another atom to fill that outer electron shell.Full Answer >
A nitrogen atom forms three covalent bonds. The number of valence electrons an atom possesses determines how many covalent bonds it can form. Since nitrogen has five valence electrons and bonds, it uses three of its five valance electrons for bonding.Full Answer >