Unit 20: Introduction to Organic and Biological Chemistry
How carbon's four bonds build everything from gasoline to a protein, and how a handful of repeating functional groups run all of it.
8 topics · 28 questions
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20.1 Alkanes and Hydrocarbon Nomenclature
- How it worksHow does counting the longest continuous carbon chain and naming its branches build an alkane's IUPAC name?
- Worked exampleFind the IUPAC name for the alkane CH3CH(CH3)CH2CH3.
- Common mistakeWhy isn't an alkane's molecular formula, like C4H10, enough by itself to specify one unique structure?
Your turn1 of 2
What is the correct IUPAC name for the alkane CH3CH(CH3)CH2CH3?20.1 Structural Isomers
- How it worksHow does rearranging the same set of atoms into a straight chain versus a branched chain create distinct structural isomers?
- Worked exampleFind the number of structural isomers possible for the molecular formula C5H12.
- Common mistakeWhy aren't structural isomers just the same molecule viewed or drawn from a different angle?
- Going furtherWhat happens to the number of possible isomers as a hydrocarbon's carbon chain gets longer and longer?
Your turn1 of 2
How many structural isomers are possible for the molecular formula C5H12?20.1 Alkenes, Alkynes, and Degree of Unsaturation
- How it worksHow does counting a molecule's degree of unsaturation reveal the number of double bonds, triple bonds, or rings hidden in its formula?
- Worked exampleFind the degree of unsaturation for a compound with the molecular formula C6H10.
- Common mistakeWhy isn't a triple bond simply twice as reactive as a double bond just because it involves more shared electron pairs?
Your turn1 of 2
Find the degree of unsaturation for a hydrocarbon with the molecular formula C8H7 (degree of unsaturation equals (2c + 2 - h) divided by 2).20.2 Alcohols and Ethers
- How it worksHow does the OH functional group's own hydrogen bonding raise an alcohol's boiling point far above a similarly sized alkane's?
- Worked exampleFind the structural difference between the alcohol ethanol and the ether dimethyl ether, both with the formula C2H6O.
- Common mistakeWhy don't ethers have the same high boiling points that alcohols do, despite both containing an oxygen atom?
Your turn1 of 2
Both ethanol (an alcohol) and dimethyl ether contain an oxygen atom, yet ethanol has a much higher boiling point. Why don't ethers share alcohols' high boiling points?20.3 Aldehydes, Ketones, and Carboxylic Acids
- How it worksHow does the carbonyl group's position, at the end of a chain or in the middle, distinguish an aldehyde from a ketone?
- How it worksWalk me through how adding an OH group to a carbonyl carbon turns an aldehyde into a carboxylic acid.
- Worked exampleFind the functional group present in the molecule CH3COOH and name the class of compound it belongs to.
- Common mistakeWhy isn't a carboxylic acid the same functional group as an aldehyde, even though both contain a carbonyl group?
Your turn1 of 2
What functional group is present in the molecule CH3COOH, and what class of compound does it belong to?20.3 Esters and Amides
- How it worksHow does a carboxylic acid reacting with an alcohol, releasing water, form the ester functional group?
- Worked exampleFind the ester and byproduct formed when acetic acid reacts with ethanol.
- Common mistakeWhy isn't an amide bond the same thing as an amine simply attached to a carbon chain?
- Ties togetherHow does the ester bond connecting fatty acids to glycerol in a fat connect back to the same condensation reaction that builds a protein's amide bonds?
Your turn1 of 2
What ester and byproduct form when acetic acid reacts with ethanol?20.4 An Introduction to Biomolecules
- How it worksHow does linking small repeating monomers together through condensation reactions build carbohydrates, proteins, and nucleic acids as polymers?
- How it worksWalk me through how amino acids link together through amide bonds to build up a protein's chain.
- Common mistakeWhy aren't lipids classified as true polymers the way proteins and carbohydrates are?
- Going furtherWhat happens to a protein's three-dimensional shape when the hydrogen bonds and other interactions holding it folded are disrupted by heat?
Your turn1 of 2
Proteins and carbohydrates are built from repeating monomer units (amino acids and monosaccharides) linked together. Why aren't lipids classified as true polymers the way proteins and carbohydrates are?20.4 Amines and Organic Nitrogen Compounds
- How it worksHow does a nitrogen atom's lone pair make an amine act as a base, the organic cousin of ammonia?
- Worked exampleFind whether the compound CH3CH2NH2 is a primary, secondary, or tertiary amine.
- Common mistakeWhy isn't every nitrogen-containing organic molecule automatically classified as an amine?
Your turn1 of 2
Is the compound CH3CH2NH2 a primary, secondary, or tertiary amine?