Organic chemistry

Intermolecular forces

Forces that exist between molecules, generally weaker than intramolecular forces.

Intramolecular forces

Forces within a molecule, such as covalent bonds, with typical bond strengths in the hundreds of thousands of kilojoules.

Ion-Dipole Forces

Attractive forces between an ion and a polar molecule, recognized as the strongest of all intermolecular forces.

Dipole-Dipole Forces

Attractive forces between polar molecules.

London Forces

The weakest intermolecular forces, also known as van der Waals dispersion forces, caused by instantaneous dipoles attracting adjacent electron clouds.

Polarizability

The ease with which an electron cloud can be deformed.

Hydrogen Bonding

A special dipole-dipole interaction between a hydrogen atom in a polar $N-H$, $O-H$, or $F-H$ bond and an electronegative $O$, $N$, or $F$ atom.

Surface Tension

The amount of energy required to stretch or increase the surface of a liquid by a unit area.

Cohesion

The intermolecular attraction between like molecules.

Adhesion

An attraction between unlike molecules.

Viscosity

A measure of a fluid's resistance to flow; higher intermolecular forces lead to high viscosity.

Unit Cell

The smallest repeating unit in a crystal that possesses all the symmetry of the entire crystal.

Covalent Network Solids

Solids where atoms are held together in large networks by covalent bonds, characterized by very high melting points (e.g., diamond and graphite).

Metallic Solids

Solids where metal nuclei float in a sea of delocalized electrons, providing high conductivity and malleability.

Charge Density

A value calculated as $\frac{\text{ionic charge}}{\text{volume}}$ that correlates with higher melting points and greater hardness.

Hydroxyl group

The $-OH$ functional group found in alcohols and phenols.

Methanol toxicity

A highly toxic substance to humans where $15\,ml$ can cause blindness and $150\,ml$ can cause death.

Polyalcohols

Alcohols containing more than one $-OH$ group, often using suffixes like -diol or -triol.

Carbonyl group

A functional group consisting of a carbon atom double-bonded to an oxygen atom ($C=O$), present in both aldehydes and ketones.

Aldehyde

A compound containing a carbonyl group located at the end of a carbon chain.

Ketone

A compound where the carbonyl group is attached to two other carbon atoms within the chain.

Carboxylic Acid

An organic compound containing a carboxyl group ($-COOH$), exhibiting the highest polarity and boiling points among functional groups.

Esterification

A condensation reaction between an alcohol and a carboxylic acid to produce an ester and water, typically catalyzed by $H_2SO_4$.

Addition Reaction

A reaction where atoms are added to a carbon-carbon double or triple bond, such as hydrogenation or hydration.

Markovnikov’s Rule

The rule stating that the hydrogen atom attaches to the carbon atom that already has more hydrogen atoms during an addition reaction.

Elimination Reaction

A reaction in which atoms are removed from an organic molecule to form a double bond; it is the reverse of an addition reaction.

Substitution Reaction

A reaction in which a hydrogen atom or functional group is replaced by a different atom or functional group.

Condensation Reaction

A reaction where two molecules combine to form a larger product while eliminating a small molecule such as water or alcohol.

Hydrolysis

A reaction in which a molecule is broken apart by adding the $OH$ and $H$ from a water molecule to either side of a bond.

Oxidation (Organic)

A reaction in which a carbon atom forms more bonds to oxygen atoms or fewer bonds to hydrogen atoms.

Reduction (Organic)

A reaction in which a carbon atom forms fewer bonds to oxygen atoms or more bonds to hydrogen atoms.

Combustion Reaction

A reaction where a compound reacts with oxygen to produce oxides, such as carbon dioxide and water vapor, and release energy.

Nomenclature for Alcohols

Alcohols are named by replacing the suffix '-e' of the corresponding alkane with '-ol', indicating the position of the hydroxyl group. For example, $C_2H_5OH$ is named ethanol.

Nomenclature for Aldehydes

Aldehydes are named by replacing the suffix '-e' of the corresponding alkane with '-al'. For example, $C_3H_6O$ is named propanal.

Nomenclature for Ketones

Ketones are named by replacing the suffix '-e' of the corresponding alkane with '-one', specifying the position of the carbonyl group. For example, $C_4H_8O$ is named butan-2-one.

Nomenclature for Carboxylic Acids

Carboxylic acids are named by replacing the suffix '-e' of the corresponding alkane with '-oic acid'. For example, $C_2H_4O_2$ is named acetic acid.

Catalysts for Esterification

Esterification typically requires an acid catalyst, commonly sulfuric acid ($H_2SO_4$), to speed up the reaction between an alcohol and a carboxylic acid.

Catalysts for Addition Reactions

Addition reactions often utilize metal catalysts such as palladium, platinum, or nickel, particularly in hydrogenation reactions.

Catalysts for Elimination Reactions

Elimination reactions may use bases like sodium hydroxide ($NaOH$) or potassium hydroxide ($KOH$) to facilitate the removal of small molecules.

Catalysts for Oxidation Reactions

Common catalysts for oxidation reactions include potassium permanganate ($KMnO_4$) or chromium trioxide ($CrO_3$), which can oxidize alcohols.

Catalysts for Reduction Reactions

Reduction reactions often use hydrogen gas in the presence of metal catalysts such as palladium or platinum to convert carbonyl compounds into alcohols.

Organic Chemistry

The branch of chemistry that focuses on the structure, properties, reactions, and synthesis of carbon-containing compounds, encompassing a vast array of substances that include hydrocarbons and their derivatives.

Urea

The first organic compound synthesized artificially in a lab in 1828 by Friedrich Wöhler; it serves as a key nitrogen-containing waste product in mammalian metabolism.

Functional Group

A specific grouping of atoms within a molecule that is responsible for the characteristic chemical reactions of that molecule; they determine the reactivity and properties of various organic compounds.

Hydrocarbon

An organic molecule composed exclusively of carbon and hydrogen atoms; hydrocarbons can be categorized as aliphatic or aromatic compounds.

Saturated Hydrocarbon

Also known as alkanes, these hydrocarbons contain only single covalent bonds between carbon atoms, resulting in the maximum number of hydrogen atoms attached to each carbon; they generally have the formula $C_nH_{2n+2}$.

Alkane

A type of saturated hydrocarbon with only single bonds between carbon atoms, illustrated by the general formula $C_nH_{2n+2}$. Reactions often involve simple substitution; catalysts are generally not needed.

Alkene

An unsaturated hydrocarbon characterized by at least one carbon-carbon double bond, following the general formula $C_nH_{2n}$. Alkenes readily undergo addition reactions which often require catalysts such as metals or acid.

Alkyne

An unsaturated hydrocarbon with at least one carbon-carbon triple bond, defined by the formula $C_nH_{2n-2}$. Alkynes are reactive and participate in various addition reactions, often catalyzed by transition metals.

Cyclic Hydrocarbon

A type of hydrocarbon where the carbon atoms are connected in a closed ring structure; can be saturated (cycloalkanes) or unsaturated (cycloalkenes), which affect their reactivity.

Alkyl Group

A group of atoms derived from an alkane by the removal of one hydrogen atom; it acts as a substituent in larger molecules and influences the compound's properties and reactivity.

Aliphatic Hydrocarbon

Hydrocarbons that consist of straight or branched chains, or cyclic forms, but do not include aromatic hydrocarbons which have a distinct structure involving resonance.

Aromatic Hydrocarbon

Organic compounds that contain conjugated ring systems, notably the benzene ring structure characterized by the formula $C_6H_6$, known for their stability and unique reactions due to resonance.

Benzene

A fundamental aromatic hydrocarbon represented by the formula $C_6H_6$; its structure showcases six carbon atoms in a cyclic arrangement with delocalized electrons, imparting remarkable stability and known for electrophilic substitution reactions.

IUPAC

Acronym for the International Union of Pure and Applied Chemistry, responsible for establishing the standard nomenclature and guidelines for organic compounds utilized by chemists worldwide.

Line Formula

A simplified representation of organic molecules where lines represent bonds and vertices represent carbon atoms; hydrogen atoms are typically omitted for clarity, but implied as needed.

Paraffins

A term associated with alkanes, referring to their lack of reactivity due to their saturated nature, often used to denote hydrocarbons resistant to reaction with strong oxidants or acids.

Phenyl Group

The term given to a benzene ring when it acts as a substituent on another molecule, contributing to the overall properties and reactivity of the larger organic compound.

Ortho

In nomenclature for aromatic compounds, 'ortho-' denotes that two substituents are located on adjacent carbon atoms of a benzene ring.

Meta

'Meta-' is used in aromatic nomenclature to indicate that two substituents are separated by one carbon atom on a benzene ring.

Para

'Para-' is employed to signify that two substituents are positioned opposite each other on a benzene ring.

Isomers

Compounds that share the same molecular formula but differ in the arrangement of atoms, leading to varied chemical and physical properties.

Constitutional Isomers

Isomeric compounds that possess the same molecular formula but differ in the connectivity of their atoms, resulting in distinct compounds.

Stereoisomers

Isomers that have the same molecular formula and connectivity of atoms but differ in their spatial arrangement, affecting their chemical behavior.

Diastereomers

A subset of stereoisomers that are not mirror images of each other, often differing in their physical properties and chemical reactivity.

Enantiomers

Stereoisomers that are non-superimposable mirror images of each other, typically involving chiral centers, resulting in unique interactions in biological systems.

Ethene (Ethylene)

A colorless gas (C2H4) used as a plant hormone to regulate fruit ripening; it is a key feedstock in the production of various plastics; reacts readily through addition reactions.

Ethyne (Acetylene)

The simplest alkyne (C2H2) known for its use as a fuel in welding, capable of producing extremely high temperatures, specifically over $3300 \text{°C}$, in combustion reactions.