HSC Chemistry — Module 7
Organic Nomenclature — Flashcards & Quiz
Organic nomenclature is the systematic naming of carbon compounds following IUPAC rules. HSC Chemistry Module 7 requires you to name and draw structures for alkanes, alkenes, alkynes, alcohols, aldehydes, ketones, carboxylic acids, amines, amides, and esters. You must identify the longest carbon chain, locate substituents, and number correctly. Exam questions test naming from structures and drawing structures from names, often including isomers. Mastering nomenclature is essential because it underpins every other organic chemistry topic in the module.
Key Points
- IUPAC nomenclature: identify the longest continuous carbon chain containing the principal functional group, number to give it the lowest locant, then list substituents alphabetically.
- Suffix hierarchy (high to low): carboxylic acid (-oic acid) > ester (-oate) > amide (-amide) > aldehyde (-al) > ketone (-one) > alcohol (-ol) > amine (-amine).
- Prefixes count carbons: meth- (1), eth- (2), prop- (3), but- (4), pent- (5), hex- (6), hept- (7), oct- (8).
- Saturation suffix: -ane (saturated), -ene (C=C), -yne (C≡C). Locants indicate the position of the double/triple bond.
- Isomers with identical molecular formulas can have very different names — always draw the structure to check your naming against connectivity.
- HSC exam skill: draw a structure from an IUPAC name and vice versa; identify ALL functional groups before assigning the principal one.
Common Mistakes to Avoid
- Not choosing the LONGEST continuous carbon chain — always extend the main chain through any straight path.
- Numbering from the wrong end — locants should be as LOW as possible for the principal functional group.
- Listing substituents in the wrong order — they should be alphabetical (ignoring "di-", "tri-" prefixes for ordering).
- Forgetting to include locants for substituents — "methylpropane" alone is ambiguous; use "2-methylpropane".
- Naming alkenes without specifying the C=C position — "butene" is wrong; "but-1-ene" or "but-2-ene" is correct.
Exam Strategy
HSC Module 7 nomenclature questions ask you to name a given structure or draw a structure from a given name. Approach: (1) find the longest chain containing the principal functional group, (2) number it to give the functional group the lowest locant, (3) identify and number substituents, (4) alphabetise substituents, (5) combine into the final name. Work in pencil first; you'll catch errors faster.
Sample Flashcards
Q1: How do you name organic compounds using IUPAC nomenclature?
1) Find the longest carbon chain (parent chain). 2) Name the parent chain: meth-, eth-, prop-, but-, pent-, hex- etc. 3) Add suffix for functional group: -ane (alkane), -ene (alkene), -ol (alcohol), -al (aldehyde), -one (ketone), -oic acid (carboxylic acid). 4) Number the chain to give substituents the lowest numbers. 5) Name substituents with position numbers.
Q2: Name the first 8 prefixes in IUPAC naming.
meth- (1C), eth- (2C), prop- (3C), but- (4C), pent- (5C), hex- (6C), hept- (7C), oct- (8C). These prefixes indicate the number of carbons in the longest continuous chain (parent chain).
Sample Quiz Questions
Q1: The prefix "prop-" indicates a three-carbon chain.
Answer: TRUE
IUPAC prefixes: meth- (1C), eth- (2C), prop- (3C), but- (4C), pent- (5C), etc.
Revision Tip
Nomenclature is muscle memory — drill 15-20 structures in a Revizi deck (mixing naming and drawing), increasing complexity over time.
Related Concepts
Last updated: March 2026 · 2 flashcards · 1 quiz questions