Properties of Hydrocarbons and Functional Groups

A set of vocabulary flashcards covering functional groups, intermolecular forces, and related physical-property terms from Chemistry 3 Module 1.2: Properties of Hydrocarbons and Functional Groups.

Functional Group

A distinctive set of bonded atoms in an organic molecule that largely determines the compound’s properties and reactivity.

Aliphatic Hydrocarbon

An organic molecule composed only of carbon and hydrogen in open-chain (alkane, alkene, alkyne) or non-aromatic cyclic forms.

Alkane

A saturated hydrocarbon containing only single C–C bonds; parent names end in “-ane.”

Alkene

An unsaturated hydrocarbon containing at least one C=C double bond; parent names end in “-ene.”

Alkyne

An unsaturated hydrocarbon with at least one C≡C triple bond; parent names end in “-yne.”

Alkyl Halide

An organic compound in which a halogen (F, Cl, Br, I) replaces a hydrogen on an alkane chain; also called haloalkane.

Ether

A compound with the functional group R-O-R′, where an oxygen bridges two carbon groups.

Alcohol

An organic molecule containing an –OH group attached to a saturated carbon; names end in “-ol.”

Phenol

A compound with an –OH group directly bonded to an aromatic ring; names often end in “-phenol.”

Ketone

A carbonyl compound in which the C=O is bonded to two carbons; names end in “-one.”

Aldehyde

A carbonyl compound with the C=O bonded to at least one hydrogen; names end in “-al.”

Carboxylic Acid

A compound containing the –COOH group; names end in “-oic acid.”

Ester

A carbonyl derivative with the group –COOR; names end in “-oate.”

Amide

A carbonyl compound featuring –CONH₂, –CONHR, or –CONR₂; names end in “-amide.”

Acid Anhydride

A molecule formed from two carboxylic acids minus water; names end in “-oic anhydride.”

Amine

A nitrogen-containing compound derived from ammonia; classified as 1°, 2°, 3° and named with “-amine.”

Nitrile

An organic molecule with a –C≡N group; names end in “-nitrile.”

Imine

A compound with a C=N double bond where nitrogen is singly bonded to carbon or hydrogen; names end in “-imine.”

Sulfide (Thioether)

An analog of an ether in which sulfur replaces oxygen (R-S-R′); named “____”

Disulfide

A compound containing an R-S-S-R′ linkage.

Sulfoxide

A sulfur-containing compound with the group R-S(=O)-R′; named “____”

Thiol

An organic compound bearing an –SH group; names end in “-thiol.”

Thioester

A carbonyl derivative where –S– replaces –O– of an ester (R-COSR′); names end in “-thioate.”

Intermolecular Forces of Attraction (IMFAs)

Forces that act between molecules; dominate physical properties such as boiling point, melting point, and solubility.

London Dispersion Forces

Weak, temporary attractions arising from instantaneous dipoles; present in all molecules and increase with chain length or molar mass.

Dipole–Dipole Forces

Attractions between permanent molecular dipoles; occur in polar compounds such as alkyl halides.

Hydrogen Bonding

A strong dipole–dipole interaction where H is bonded to N or O (or F) and attracted to a lone pair on another electronegative atom.

Boiling Point

The temperature at which a liquid’s vapor pressure equals external pressure; rises with stronger IMFAs.

Melting Point

The temperature at which a solid and liquid are in equilibrium; increases with stronger IMFAs and better molecular packing.

Density (of organic compounds)

Mass per unit volume; affected by molecular mass and packing—branched molecules are generally less dense than linear ones.

Solubility

Extent to which a substance dissolves in a solvent; governed by similarity and strength of intermolecular forces.

“Like Dissolves Like”

Rule stating that substances with similar polarity and IMFAs are mutually soluble (e.g., polar solutes in polar solvents).

Chain Length Effect

Longer hydrocarbon chains strengthen dispersion forces, raising boiling/melting points and lowering water solubility.

Branching Effect

Branching reduces surface area, weakens dispersion forces, lowers boiling point, and decreases density compared with straight chains.