Lesson 3: Nomenclature & Physical Properties of Organic Molecules

Alkanes

Hydrocarbon containing only single bonds

Hydrocarbon

Compound composed of only carbon and hydrogen atoms

Straight-chain alkanes

Alkanes in which the carbons form a continuous chain with no branches

Methane

Straight-chain alkane with 1 carbon

Ethane

Straight-chain alkane with 2 carbons

Propane

Straight-chain alkane with 3 carbons

Butane

Straight-chain alkane with 4 carbons

Pentane

Straight-chain alkane with 5 carbons

Hexane

Straight-chain alkane with 6 carbons

Heptane

Straight-chain alkane with 7 carbons

Octane

Straight-chain alkane with 8 carbons

Nonane

Straight-chain alkane with 9 carbons

Decane

Straight-chain alkane with 10 carbons

Homologous series

Family of compounds in which each member has one more methylene (CH2) group than the one before it

$C_nH_{2n+2}$

General molecular formula for an acyclic alkane

Constitutional isomers

Compounds that have the same molecular formula but differ in the way the atoms are connected

iso-

Carbon bonded to a hydrogen and two $CH_3$ groups

Alkyl groups/substituents

Group formed by removing a hydrogen from an alkane

R

Letter used to indicate any alkyl group

Alcohol

R — OH

-amine

R — $NH_2$

X

Letter used to indicate any alkyl group

Alkyl halide

R — X

Ether

R — O — R

Primary

Carbon bonded to one other carbon

Secondary

Carbon bonded to two other carbons

Tertiary

Carbon bonded to three other carbons

Sec-

Group has a hydrogen removed from a secondary carbon

Tert-

Group has a hydrogen removed from a tertiary carbon

Parent hydrocarbon

Longest continuous carbon chain

$$C_nH_{2n}$$

General molecular formula for cycloalkanes