AP BIOLOGY

Detailed explanation-1: -Carbon contains four electrons in its outer shell. Therefore, it can form four covalent bonds with other atoms or molecules. The simplest organic carbon molecule is methane (CH4), in which four hydrogen atoms bind to a carbon atom (Figure 1). However, structures that are more complex are made using carbon.

Detailed explanation-2: -Atoms bond by sharing electrons. In a typical bond two electrons are shared, one from each of the atoms involved. Carbon has four such sharable electrons of its own, so it tends to form four bonds to other atoms.

Detailed explanation-3: -For making four bonds, eight electrons would have to be squeezed in and such a system is highly unstable energetically. So, C-C quadruple bonds do not exist.

Detailed explanation-4: -Among chemistry’s most fundamental concepts is that carbon is tetravalent and forms four bonds to other atoms.

Detailed explanation-5: -Carbon’s ability to form up to four covalent bonds means chains and rings of carbon can form. This means many different molecular structures can be built from this versatile atom. Carbon can easily bond to lots of other elements, including hydrogen, oxygen and the halogens.