Search results
Results From The WOW.Com Content Network
Propylene, also known as propene, is an unsaturated organic compound with the chemical formula CH 3 CH=CH 2.It has one double bond, and is the second simplest member of the alkene class of hydrocarbons.
Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist between two different elements: for example, in a carbonyl group between a carbon atom and an oxygen atom. Other common double bonds are found in azo compounds (N=N), imines (C=N), and sulfoxides (S=O). In a skeletal formula, a double bond ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
A carbon–carbon double bond consists of a sigma bond and a pi bond. This double bond is stronger than a single covalent bond (611 kJ/mol for C=C vs. 347 kJ/mol for C–C), [1] but not twice as strong. Double bonds are shorter than single bonds with an average bond length of 1.33 Å (133 pm) vs 1.53 Å for a typical C-C single bond. [7]
The term itself is a general representation of electron density or configuration resembling a similar "bent" structure within small ring molecules, such as cyclopropane (C 3 H 6) or as a representation of double or triple bonds within a compound that is an alternative to the sigma and pi bond model.
A double bond between two given atoms consists of one σ and one π bond, and a triple bond is one σ and two π bonds. [8] Covalent bonds are also affected by the electronegativity of the connected atoms which determines the chemical polarity of the bond. Two atoms with equal electronegativity will make nonpolar covalent bonds such as H–H.
The triangular structure of cyclopropane requires the bond angles between carbon-carbon covalent bonds to be 60°. The molecule has D 3h molecular symmetry. The C-C distances are 151 pm versus 153-155 pm. [15] [16] Despite their shortness, the C-C bonds in cyclopropane are weakened by 34 kcal/mol vs ordinary C-C bonds.
For hydrocarbons, the DBE (or IHD) tells us the number of rings and/or extra bonds in a non-saturated structure, which equals the number of hydrogen pairs that are required to make the structure saturated, simply because joining two elements to form a ring or adding one extra bond (e.g., a single bond changed to a double bond) in a structure reduces the need for two H's.