Term
| 3 Reactions Alkanes Can Undergo |
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Definition
1)Combustion
2)Cracking and Hydrocracking
3)Halogenation |
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Term
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Definition
Rapid oxidation that takes place at high temperatures
converting alkanes to carbon dioxide and water
little control is possible except for control of temp
CnH(2n+2) + excess O2 >heat> nCO2 + (n+1)H2O |
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Term
| Cracking and Hydrocracking |
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Definition
Large hydrocarbons at high temps produce smaller hydrocarbons
-catalyst |
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Term
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Definition
heat or light usually needed to initiate
alkanes reacting with halogens to form alkyl halides
fluorine—to fast to control
Iodine—reacts slowly or not at all |
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Term
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Definition
-Most stable cyclohexane conformation
-all C-C bonds are 109.5 degrees |
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Term
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Definition
-bonds angles of 109.5 degrees and avoids angle strain
-suffers from torsional strain because there is an eclipsing of bonds
-eclipsing causes flagpole hydrogens to interfere with one another |
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Definition
-more stable than boat
-flagpole hydrogens move away from each other so the eclipsing bonds are reduced
-twist boat is lower in energy than boat |
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Definition
| -highest energy and the most unstable |
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Term
| chair-chair interconversion "ring flip" |
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Definition
-changes axial to equatorial and vice versa
-figure 3-23 |
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Definition
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Term
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Definition
point out from the ring—equatorial is more stable than axial
*equatorial bonds have lower energy so the more equatorial bonds are more stable |
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Definition
strain you get when things are eclipsed
—resistance to twisting |
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Term
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Definition
| when C-C bonds do not have angles of 109.5 |
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Definition
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Definition
| groups so close that their electron clouds experience a strong repulsion |
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Term
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Definition
-most common
-chare two adjacent carbon atoms and the bond between them
bicyclo[#.#.#]... |
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Term
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Definition
-share one or more nonadjacent carbon atoms
bicylo[#.#.#]... |
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Definition
two rings share only one carbon atom, relatively rare
spiro[#.#.#]... |
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Term
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Definition
| Non-superimposable mirror-image molecules; mirror-image isomers |
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Definition
| different compounds with the same molecular formula |
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Definition
| steroisomers that are not mirror images |
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Definition
| a mixture of equal quantities of enantiomers |
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Term
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Definition
generates a reactive intermediate
—always require light or heat to trigger |
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Term
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Definition
reactive intermediates react with a stable molecule to form a product and another reactive intermediate
**one RI and radical on each side of equation |
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Term
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Definition
side reactions that destroy reactive intermediates and tend to slow or stop the reaction
**getting rid of radicals |
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Term
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Definition
| a short-lived species that is never present in high concentration because it reacts as quickly as it is formed |
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Definition
| species with unpaired electron |
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Term
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Definition
| a bond breaks so that each bonded atom gets an electron |
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Definition
| one of the atoms retains both electrons |
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Definition
| species that contains a carbon atom with a positive charge |
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Definition
| species that contains a a pair of nonbonding electron and are negatively charged |
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Definition
| divalent that has two nonbonding electrons on the divalent carbon atom |
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Definition
| slowest step in a multistep sequence of reactions |
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Definition
| a measure of the heat energy in a system |
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Definition
| consuming energy (positive H) |
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Definition
| giving off heat (Negtive H) |
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Definition
| a substance that increases the rate of a reaction (By lowering Ea) without being consumed in the reaction |
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Term
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Definition
| Related species (on a reaction-energy diagram) that are closer in edgy are also closer in structure. In an exothermic reaction, the transition state is closer to the reactants in energy and in structure. In an endothermic reaction, the transition state is closer to the products in energy and in structure. |
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Definition
| 4 different connected atoms |
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Definition
| compound have two C=C DB that meet at a single carbon ; many allenes are chiral |
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Definition
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Definition
| they can be placed atop one another and the three-dimensional position of each atom of one molecule coincides with the equivalent atom of the other molecule |
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Definition
cut in half and is the same on both sides—a chiral
**any molecule that has a n internal mirror place of symmetry cannoth be chiral, even though it may contain asymmetric carbon atoms |
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Term
| Cahn-Ingold-Prelog convention |
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Definition
(R&S system) naming the configurations of chirality centers
1. assign priority
R=clockwise
S=Counterclockwise |
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Term
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Definition
measure of the plane rotation
*can only have with chiral compounds
*only chiral compounds are optically active |
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Term
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Definition
| achiral compounds with chiral centers |
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Term
| Ways to resolve diastereomers |
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Definition
| distillation, recrystallazation, chromatography |
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Term
| Way to Resolve Enantiomers |
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Definition
1) chemical resolution
2)chromatography |
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Term
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Definition
| separation of enantiomers |
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Definition
| a chiral probe that is necessary for the resolution of enantiomers |
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Term
| Chemical Resolution of Enantiomers |
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Definition
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Term
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Definition
| measures the rotation of polarized light |
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Term
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Definition
| substances that rotate the place eof polarized light |
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Definition
| rotation of the place of polarized light |
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Definition
| (d) rotating the place of polarized light clockwise |
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Definition
| a measure of a compound's ability to ratite the plane of polarized light **know formula |
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Term
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Definition
the specific toation of mixture of two eneantiomers, expressed as percentage of the specific rotation of one of the pure enantiomers
**Known formula |
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Definition
| (-) (l) rotating the place of polarized light counterclockwise |
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