Organic Chemistry Study Guide – Functional
Groups, Nomenclature & Isomerism|Questions
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Alkanes
- First four alkanes are methane (CH4), Ethane (C2H6), Propane (C3H8), and Butane (C4H10)
- single Bonded
Alkenes and Alkynes
- Contain double and triple bonds respectively.
Alcohols
- contain Hydroxyl group (OH)
- suffix ol or hydroxy if a higher priority group is present
- Diols contain two hydroxyl groups.
* Geminal: 2 Hydroxyl groups on the same carbon
* Vicinal: on adjacent carbons
Carbonyl group
Common Names of Aldehydes
- suffix al
- Common names include
* formaldehyde for methanal (R = H)
* Acetyldehyde for ethanal ( R = CH3)
* Propionaldehyde for propanal (R = CH3CH2)
Aldehyde vs. Ketones Terminal group
- An aldehyde has a terminal functional group due to the one hydrogen
- Ketone has two alkyl groups so it's never a terminal group.
Naming cyclic Aldehydes
Aldehyde Nomenclature: Methanal
Formaldehyde
,Aldehyde Nomenclature: Ethanal
Acetaldehyde
Aldehyde Nomenclature: Propanal
Propionaldehyde
Aldehyde Nomenclature: Butanal
Butyraldehyde
Aldehyde Nomenclature: Pentanal
Valeraldehyde
Naming Ketones: 2-propanone
- Dimethyl ketone
- Acetone
Naming Ketones: 2-butanone
- ethylmethylketone
Naming Ketones: 3-oxobutanoic Acid
Naming Ketones: Cyclopentanone
Common Names for Ketones
- suffix one
- Acetone (dimethylketone; 2- propanone) ; smallest ketone; similar as the figure
- 2 pentanone (R= CH3CH2CH2)
3-butene-2-one
- Naming ketones
- methylvinylketone
Carboxylic Acids and Derivatives
- Contain both carbonyl group C=O and hydroxyl group (OH)
- most oxidized group that appear on the MCAT
- Suffix: Oic acid
- Methanoic acid (Formic Acid)
- Ethanoic acid (acetic acid)
- Propanoic Acid (Propanoic Acid)
, Ester
- Carboxylic acid derivative
- OH is replaced with OR, an alkoxy group
Amides
- Carboxylic acid derivative
- OH is replaced with an amino group
Anhydrides
- Carboxylic acid derivative
- formed by dehydration of 2 carboxylic acids
* Symmetric = same acid
* asymmetric = two different acids
* cyclic = intramolecular reaction of a dicarboxylic acid
Summary of Functional Groups
Carboxylic acid > anhydride > Ester > Amide > Aldehyde > Ketone > Alcohol > alkene or alkyne
> alkane
Structural Isomer
- Share only a molecular formula
- They have different physical and chemical properties
Conformational Isomer
- Same molecule, differ in rotation around single pi bonds.
Newman's Projection
- Anti staggered isomer has the lowest energy
- Staggered isomer has the highest energy
Configurational Isomer
- Can be interconverted only by breaking bonds.
- consist of two categories:
* Enantiomers: nonsuperimposable mirror image and thus have opposite stereochemistry at
every chiral carbon.
* Diasteromer: non- mirror image stereoisomers; differ at some but not all chiral centers. Ex)
cis - trans isomers
Diastereomers
Groups, Nomenclature & Isomerism|Questions
Verified and Complete with A+ Graded
Rationales Latest Updated 2026
Alkanes
- First four alkanes are methane (CH4), Ethane (C2H6), Propane (C3H8), and Butane (C4H10)
- single Bonded
Alkenes and Alkynes
- Contain double and triple bonds respectively.
Alcohols
- contain Hydroxyl group (OH)
- suffix ol or hydroxy if a higher priority group is present
- Diols contain two hydroxyl groups.
* Geminal: 2 Hydroxyl groups on the same carbon
* Vicinal: on adjacent carbons
Carbonyl group
Common Names of Aldehydes
- suffix al
- Common names include
* formaldehyde for methanal (R = H)
* Acetyldehyde for ethanal ( R = CH3)
* Propionaldehyde for propanal (R = CH3CH2)
Aldehyde vs. Ketones Terminal group
- An aldehyde has a terminal functional group due to the one hydrogen
- Ketone has two alkyl groups so it's never a terminal group.
Naming cyclic Aldehydes
Aldehyde Nomenclature: Methanal
Formaldehyde
,Aldehyde Nomenclature: Ethanal
Acetaldehyde
Aldehyde Nomenclature: Propanal
Propionaldehyde
Aldehyde Nomenclature: Butanal
Butyraldehyde
Aldehyde Nomenclature: Pentanal
Valeraldehyde
Naming Ketones: 2-propanone
- Dimethyl ketone
- Acetone
Naming Ketones: 2-butanone
- ethylmethylketone
Naming Ketones: 3-oxobutanoic Acid
Naming Ketones: Cyclopentanone
Common Names for Ketones
- suffix one
- Acetone (dimethylketone; 2- propanone) ; smallest ketone; similar as the figure
- 2 pentanone (R= CH3CH2CH2)
3-butene-2-one
- Naming ketones
- methylvinylketone
Carboxylic Acids and Derivatives
- Contain both carbonyl group C=O and hydroxyl group (OH)
- most oxidized group that appear on the MCAT
- Suffix: Oic acid
- Methanoic acid (Formic Acid)
- Ethanoic acid (acetic acid)
- Propanoic Acid (Propanoic Acid)
, Ester
- Carboxylic acid derivative
- OH is replaced with OR, an alkoxy group
Amides
- Carboxylic acid derivative
- OH is replaced with an amino group
Anhydrides
- Carboxylic acid derivative
- formed by dehydration of 2 carboxylic acids
* Symmetric = same acid
* asymmetric = two different acids
* cyclic = intramolecular reaction of a dicarboxylic acid
Summary of Functional Groups
Carboxylic acid > anhydride > Ester > Amide > Aldehyde > Ketone > Alcohol > alkene or alkyne
> alkane
Structural Isomer
- Share only a molecular formula
- They have different physical and chemical properties
Conformational Isomer
- Same molecule, differ in rotation around single pi bonds.
Newman's Projection
- Anti staggered isomer has the lowest energy
- Staggered isomer has the highest energy
Configurational Isomer
- Can be interconverted only by breaking bonds.
- consist of two categories:
* Enantiomers: nonsuperimposable mirror image and thus have opposite stereochemistry at
every chiral carbon.
* Diasteromer: non- mirror image stereoisomers; differ at some but not all chiral centers. Ex)
cis - trans isomers
Diastereomers
