Chem final Flashcards
What are Constitutional isomers?
Constitutional isomers do not have the same atom to atom connectivity. They can be different in the type of functional group, position of functional group, or the skeleton.
What are Stereoisomers?
Stereoisomers have the same atom to atom connectivity.
What are Conformational isomers?
Conformational isomers have the same atom to atom connectivity and they are rotated about a single bond.
What are Configurational isomers?
Configurational isomers are a type of stereoisomers have the but they cannot be rotated about a single bond
What are Geometric isomers?
Also known as cis/trans isomers. They cannot be rotated about a single bond due to double bonds or a ring.
Trans (E) double bonds
Double bonds have groups bonded on opposite sides.
Cis (Z) double bonds
Double bonds have groups bonded on the same side.
What are Optical Isomers?
Optical isomers are also a type of Stereoisomer. The isomerization is not restricted to rotation.
What are Enantiomers?
Enantiomers are the most common form of Optical isomers. They have a single chiral center and can be drawn as non-superimposable mirror images.
What are Diastereomers?
Diastereomers are another kind of Optical isomer that are less common. They have multiple chiral centers and the locations of functional groups is changed.
What is Valence Bond Theory?
Valence Bond Theory describes a covalent bond as the overlap of half-filled atomic orbitals each containing a single electron. This overlap yields a pair of electrons shared between the two bonded atoms.
What produces a sigma bond?
The overlap of two s orbitals, the overlap of an s and a p orbital, and the end-to-end overlap of two p orbitals all produce sigma bonds.
What are sigma bonds?
In Valence Bond Theory single bonds in Lewis Structures are described as sigma bonds. A sigma bond is a covalent bond where the electron density concentrates along the internuclear axis (a line between the nuclei passes through the center of the overlap region.
What is a pi bond?
A pi bond is a type of covalent bond that results from the side-by-side overlap of two p orbitals. In a pi bond, the regions of orbital overlap lie on opposite sides of the internuclear axis. Along the axis itself, there is a node.
Types of bonds in a bond
All single bonds are sigma bonds. Multiple bonds consist of both sigma and pi bonds. Between any two atoms, the first bond that forms will always be a sigma bond, however there can only be one sigma bond in any given location so in a multiple bond there will only be one sigma bond.
How are pi bonds and sigma bonds similar and how are they different?
Similarities: both types of bonds result from overlap of atomic orbitals on adjacent atoms and contain a maximum of two electrons
Differences: sigma bonds are stronger and result from end-to-end overlap and all single bonds are sigma bonds; pi bonds between the same two atoms are weaker because they result from side-by-side overlap, and multiple bonds contain one or more pi bonds (in addition to a sigma bond)
What is hybridization?
When atoms bond together in a molecule, their wave functions combine to produce new mathematical descriptions that have different shapes. The combining of wave functions is hybridization. The resulting orbital are called hybrid orbitals.
SP Hybridization
Any central atom surrounded by just two regions of valence electron density in a molecule will exhibit sp hybridization. (any atom with only two electron domains)
SP2 Hybridization
Any central atom with three domain of electron density including lone pairs will consist of a set of three SP2 orbitals and one unhybridized P orbital. It involves the mixing of on s orbital and two p orbitals, forming a trigonal planar geometry resulting in the formation of three identical hybrid orbitals.
SP3 Hybridization
