Topic 10: Organic Chemistry Flashcards
What is a homologous series?
A series of continuous compounds of the same family with the same general formula, which differ from each other by a common structural unit
What trend to members of a homologous series show for physical properties?
Gradiation in physical properties within the series due to gradual increase in weight and size, like boiling points
What trend do members of a homologous series show for chemical properties?
Similar chemical properties within the series as all compounds in the series have the same functional group (the reactive part)
Successive members of a homologous group differ by…
1 CH2 group
How are members of a homologous series named?
Prefix (number of C atoms in longest chain) and suffix (homologous series to which the compound belongs)
What are the three homologous series?
alkanes, alkenes, alkynes
What is an alkane? What suffix and formula are used?
Saturated hydrocarbons with only single C-C bonds. C(n)H(2n+2). Suffix: -ane
What is an alkene? What suffix and formula are used?
Unsaturated Hydrocarbons with at least one double carbon carbon bond. C(n)H(2n). -ene
What is an alkyne? What suffix and formula are used?
Unsaturated hydrocarbons with at least one triple carbon carbon bond. C(n)H(2n-2). -yne
List, in order of 1-10, the prefixes used to determine the number of carbon atoms in the longest carbon chain
1: meth
2: eth
3: prop
4: but
5: pent
6: hex
7: hept
8: oct
9: non
10: dec
What is the formula for a methyl, ethyl, and propyl group?
Methyl: CH3
Ethyl: CH2CH3
Propyl: CH2CH2CH3
For a cyclic alkane, what prefix is added?
cyclo-
What are four other rules for naming organic molecules?
Use the longest Carbon chain when naming. Groups go on the lowest number carbon. Organize groups by alphabetical order. Use di, tri, tetra, penta, and hexa to determine the number of the same functional group
Functional groups determine…
The specific chemical properties of a molecule, which in turn determines the kind of reactions it undergoes
What is benzene? What is its structural formula? What is its C:H ratio, and why is that significant?
An aromatic, unsaturated hydrocarbon w/ formula C6H6. 1:1 ratio of C:H means that it is even more unsaturated than alkenes or alkynes
Benzene molecules are also named…
They are called “aromatic” because…
Do benzene molecules have isomers? Do they undergo addition reactions?
Arenes. Aromatic because they are typically fragrant. No isomers. Reluctant to undergo addition reactions.
What is a structural isomer? Give an example.
Molecules that have the same formula but different atomic arrangement, therefore unique properties. Ex: C4H8 can be 1-butene or 2-butene, depending on where the double bond is.
The drawing of a benzene ring shows alternating C-C and C=C bonds. What is the actual structure of a benzene ring?
Reasonance hybrid. It has equal bond lengths that are the average of the double and single bond lengths.
What is an electrophile? How does that relate to benzene?
An e- deficient species. Benzene can undergo electrophilic reactions in which a Hydrogen is replaced by another group
What is homolytic bond fission?
A covalent bond breaks with each atom taking one e- from the bond. Results in the formation of highly reactive free radicals with unpaired e-
What is heterolytic bond fission?
A covalent bond breaks and one atom takes both e-. Results in the formation of an anion and a cation. The more electronegative atom usually takes the 2e-.
What is the difference between primary, secondary, and tertiary carbon atoms?
Primary carbon atoms are bonded to zero or one other C atom.
Secondary is bonded to two other C atoms.
Tertiary=3 other C atoms
Are alkanes typically reactive? Why or why not?
Relatively unreactive due to strong, nonpolar C-H bond
Can alkanes undergo combustion?
Yes
What does alkane combustion produce?
CO2, H2O (if oxygen is in excess)
What color flame does complete combustion produce?
blue