Organic Chemistry Flashcards
What is an organic molecule? What are the main sources of organic molecules?
- Organic molecule: Molecules containing Carbon atoms(that are generally covalently bonded to other carbon/hydrogen atoms)
- Can contain other atoms - Exceptions: Elemental Carbon(s), Oxides of carbon(ex. CO2, CO), Most ionic compounds(except CH3COONa)
- Sources of organic molecules: Living things, fossil fuels
What is a hydrocarbon?
Hydrocarbons are organic molecules containing only Carbon and Hydrogen
What is an alkane?
An alkane is a hydrocarbon that contains only single bonds.
What is a homologous series?
A homologous series is a series of molecules that contain one extra carbon in the parent chain than the molecule before
- Carbons have to connect to each other
- Ex. Ethane is part of the same homologous series as methane
What is a structural isomer? How can you determine if two molecules are structural isomers of each other?
Structural isomers have an identical molecular formula but a different structure.
How to determine structural isomers
-Name the molecule: If the names are different, you have two different isomers
- Units of saturation have to be the same(1 unit of saturation = 2 H’s missing from standard alkane)
- Same number of Carbons
What are the functional groups and their subgroups in organic molecules? Create a flow chart.
- Hydrocarbons
(a) Alkanes
(b) Alkenes
(c) Alkynes
(d) Aromatics - Organic Halides
What is a heteroatom?
A heteroatom is an atom that is not a C or H inside an organic molecule.
What are the three ways that an organic molecule can be drawn/expressed?
- Complete structural: All the C’s and H’s are written out with the bonds drawn between them
- Condensed structural: Only the letters; Condensed structural is based on the complete structural drawing and you write it out by going from left to write and then condensing the molecules you see(looking at the H’s connected to each carbon atom in the parent chain and also branches). Include subscripts if the same subset of molecules are right beside each other.
- Bond line notation
What are the three intermolecular forces?
- London Dispersion forces: Created by temporary dipoles caused by uneven spread of electron in the molecules. LDF is proportionate to the number of electrons in the molecule(more electrons = more LDF)
- Dipole-Dipole: Polar molecules with permanent dipoles
- Conditions for polarity: (1) molecules can’t be symmetrical(dipoles would cancel themselves out, (2) electronegative atoms need to be present - Hydrogen bons: H bonded directly to N, F, or O
What is the generic molecular formula for an alkane?
C(n)H(2n+2)
What are the physical properties of alkanes?
Physical Properties
- Have only LDF, so low melting and boiling points. As you go down homologous series, mp and bp increase as LDF increases
- Solubility: Like dissolves like
What are the chemical properties of alkanes?
Alkanes can combust and can participate in substitution reactions.
What determines solubility? What does “like dissolves like” mean?
- Non polar will dissolve non polar
- Polar without H-bonds will dissolve polar without H-bonds
- Polar with H-bonds will dissolve polar with H-bonds
What is the prefix for 2 carbons?
eth
What is the prefix for 1 carbon?
meth
What happens if there is a tie when numbering the parent chain(for alkanes, alkenes, and alkynes)?
The alphabetically lower branch gets the smaller number(ethyl would get lower number than methyl if there is a tie when numbering the branches)
What is the naming format/layout for branches ?
(Locant)-(Prefix for # of C’s)yl
If there are more than one of the same branches:
(Locant#1),(Locant#2)-(prefix)(# of C’s)yl
prefix: di, tri, tetra
What is the chemical formula for cycloalkanes?
C(n)H(2n)
How many hydrogens are lost for each extra feature(DB/TB/Cyclo)?
2 Hydrogens
how do you name an alkane?
- Find the longest chain of carbons, called the parent chain
- Number the parent chain so that the branches have the lowest # possible
- Name the branches in alphabetical order
(Locant)-(Prefix for # of C’s)yl - Name the parent chain
(# of carbons)ane
NO SPACE
List out the prefix’s for the number of carbons, to ten carbons.
1-meth
2-eth
3-prop
4-but
5-pent
6-hex
7-hept
8-oct
9-non
10-dec
What is the nomenclature for cycloalkanes?
Simple branching: ring is parent, number branches alphabetically
(branches)cyclo(#of carbons)ane
Ex. 1-ethyl-3-methylcyclopentane
Complex branching(when ring is not parent): alphabetize branches, REMEMBER THAT THE WORD “CYCLO” IS PART OF ALPHABETIZATION
Ex. 6-cyclopropyl-3-ethyl-4-methyloctane
What is an alkene?
A hydrocarbon with one of more double bonds between the carbons
What are the physical and chemical properties of cycloalkanes?
Same as SIMILIAR SIZED alkanes:
Physical Properties
- Have only LDF, so low melting and boiling points. As you go down homologous series, mp and bp increase as LDF increases
- Solubility: Like dissolves like
What are the physical and chemical properties of alkenes?
Physical: Have similar mp/bp etc. to similar sized alkanes because there is only LDF. If anything the mp/bp can be slightly higher. alkenes have low solubility in water and high solubility in a non polar solvent.
Chemical: Can combust and participate in addition reactions
What is the nomenclature of alkenes?
- DB has a higher priority than SB
Higher priority means:
-Parent chain is the lowest chain of carbons that contains the priority feature
-When numbering the parent chain, the priority feature gets the smallest number possible. If there is a tie, the branches get the lowest set if numbers possible. If there is another tie, alphabetization.
The branching nomenclature stays the same. The parent suffix changes:
for 1 DB: (# of C’s)-(locant)-ene
For <1 DB: (# of C’s)a-(locants)-(di/tri/tetra)ene
What is the nomenclature for a cycloalkene?
The double bond is always in position 1 or 2 so no locant required.
What is an alkene?
A hydrocarbon with one or more double bonds between carbons
Unlike single bonds, double bonds can have ______________(1) isomers. This is because ___________________(2).
(1) Geometric
(2) Single bonds can rotate while double bonds can not
What is the difference between cis and trans isomers?
Groups are connected to the double bond in opposite directions: trans isomers
Groups are connected to the double bond in same directions: cis isomers
What is the chemical formula for cycloalkenes?
C(n)H(2n-2)
What is an alkyne?
One or more triple bonds in a hydrocarbon
What is the nomenclature for an alkyne?
- Same priority as a double bond, just change the ending to -yne
What are the chemical and physical properties of alkynes?
Physical Properties: Similar mp and bp to alkane, dissolve in non polar solvents, won’t dissolve in polar solvents
Chemical properties: combustion and addition reactions
What is the order of reactivity for alkenes, alkynes, and alkanes?
alkynes>alkene>alkane
How many units of saturation is a TB?
2 units. Rings and DB are 1.
What does it mean if a molecule is saturated/unsaturated?
saturated: a molecule is saturated if all carbon to carbon bond are single bonds
Unsaturated: a molecule is unsaturated if there are double or triple bonds
What is an aromatic?
Molecules that contain benzene. Benzene structures are like an average of the two resonance structures that can be created, so you put a circle inside the molecule
hex
What is an aliphatic?
Not aromatic(no benzene ring)
What are the physical and chemical properties of benzenes?
Physical: LDF only, so similar to other hydrocarbons(alkanes, alkenes, alkynes) of similar size(same # of carbons)
Chemical: combustion and substitution
How can you tell if a molecule is aromatic?
If the name has benzene or phenyl
Are aromatic molecules saturated or unsaturated?
neither
The original source of fossil fuels is the _______(1)?
sun
What is one consequence of organic molecules?
Greenhouse gases are made of some organic molecules. Greenhouse gases allow sunlight to pass through them bu then block infrared radiation from returning to space.
How can fractional distillation be used to separate crude oil?
1.Crude oil is turned into gas
2. the Gas rises up the lids
3. Crude oil condenses at the top
In the first subsection, large hydrocarbons condense. They have more LDF to pull them together and condense
Smaller hydrocarbons come off at the top because lower LDF nasal not enough attraction to condense until more heat energy is removed.
What is cracking?
Making large hydrocarbons smaller
- hydrocracking and ethane cracking
How do you separate oil, water, and sand from oil sands? What is this process called?
Dissolve them into a polar substance such as water and a layer of oil will form on the top.
This is called solvent extraction which uses the property of like dissolves like
How do you know when to use fractional distillation and solvent extraction?
Fractional distillation: Different sizes of molecules
Solvent extraction: Polar and non polar molecules
What is incomplete and complete combustion?
Complete:
- Abundant O2
- Clean burning flame, no soot produced
- Blue flame, almost, colorless
- Hotter
- CO2 prduced
Incomplete:
- Limited O2
- Smoke and soot
- Yellow orange flame
- Not as hot
- CO produced
What are organic halides?
A molecules where a halogen atom bonds with a hydrocarbon molecule, have a structural formula of R-X
What are the physical and chemical properties of organic halideS?
Physical: LDF and usually dipole dipole(unless molecule is symmetrical), higher melting and boiling points than a similar hydrocarbon. Polar with no H bond so great solubility in polar with no hydrogen bonding. Can sometimes dissolve in non polar solvents to some extent as the hydrocarbon chain increases in length.
Chemical: Substitution, elimination
What is the nomenclature for organic halides?
locate-atom type-o-parent chain name
What is a substitution reaction?
(alkane/benzene) + X2 -> Organic halide + HX
X: Halogen
What is a nucleophilic substitution?
Alkane with leaving group + a molecule that has lone pairs –> replace the two molecules in their exact spots
What is an alcohol and what group can be used to identify it?
- Anything with an OH
- Can be identifies by a hydroxyl group(R-O-H)
What are the physical and chemical properties of alcohols?
Physical properties:
- LDF, dipole-dipole(polar), hydrogen bonds
- Higher melting and boiling points in comparison to similar organic halides and alkanes
- Solubility: Best solubility in polar solvents with hydrogen bonding. If the hydrocarbon chain makes a large enough non-polar end, some may dissolve a little in non-polar solvents
Chemical properties:
- Substitution, elimination, esterification
What is the nomenclature for alcohols?
- The alcohol has a higher priority than DB or TB
Parent name: (# of C)(an/en/yn)-locant-ol
(# of C)(an/en/yn)e-___, _____-(di/tri/tetra)ol
What is an addition reaction?
DB/TB + small molecules -> SB/DB
H2(catalyst: Pt, Pd, Ni)
H2O(H+ catalyst): H would go on one carbon and OH on the other
X2
HX
What is a saturation test?
Adding bromine to determine if a substance is saturated or unsaturated
Unsaturated: colorless soluton
otherwise: saturated(usually a yellow color)
How can alcohols be classified?
Primary: 1 carbon bonded to the OH
Secondary: 2 carbons bonded to the OG
Tertiary: 3 carbons
What is an elimination reaction?
- Going from a SB/DB to a DB/TB by removing a small molecule
2 cases:
- Alcohol with an acid(and heat)
- Organic halide with a base(and heat)
What is an elimination reaction?
- Going from a SB/DB to a DB/TB by removing a small molecule
2 cases:
- Alcohol with an acid(and heat)
- Forms new molecule and water
- Organic halide with a base(and heat)
- from new molecule, heteroatom, and water
What is a synthesis?
Multiple steps to get a desired product
What is a carboxylic acid?
RCOOH
- C double bonded to oxygen
What are the physical/chemical properties of carboxylic acids?
- LDF, dipole-dipole, H-bonds, high mp/bp compared to similarily sized hydrocarbons
- Soluble in polar with H-bonds if hydrocarbon stays small. Soluble in non polar if hydrocarbon chain is long
- Can participate in estrification reactions
What is the nomenclature for carboxylic acids?
- Higher priority than an alcohol
(parent name)(an/en/yn)oic acid
What is an ester?
RCOOR’
- R double bonded to oxygen(not OR’)
What are the physical and chemical properties of esters?
- LDF, dipole dipole: mp/bp is lower than carboxycylic acids and alcohols but higher than similarly sized alkanes
-Partially water soluble: Although they do not have H bonds, they can use their oxygens to participate in H-bodnign with water
-Solubility in water decreases as hydrocarbon chain becomes longer
- Sweet and often fruity scents
-Made through esterification
What is the nomenclature for esters?
- Same priority as carboxylic acid
(w/out double bond)yl. (parent name)rate
What is an esterification reaction?
Carbox. acid +alcohol -(H+)-> ester + H2O
What is a condensation reaction?
2 smaller molecules into a larger molecule with the removal of water
What is a polymer?
A large structure made out of repeating parts. The part that repeats over and over is called a monomer.
What is an addition polymer?
Start with a DB/TB in the monomer and end with an all carbon backbone
What are the three types of condensation polymers?
- Polyester
- Polyamide
- Polysaccharide
What is a polyester?
Based off of ester functional group
Monomers will have to have alcohols and carboxcylic acids
What is a polyamide?
Nitrogen and carboxylic groups
What is a polysaccharides?
Sugar rings bonded together
