IGCSE Chemistry - Organic Chemistry Flashcards

Flashcards covering Topic 4 Organic Chemistry concepts from the IGCSE Chemistry Edexcel specification.

Hydrocarbon

A chemical compound that consists entirely of hydrogen and carbon atoms.

Empirical Formula

A chemical formula showing the simplest possible whole-number ratio of atoms in a molecule.

Molecular Formula

A chemical formula showing the actual number of atoms of each element in a molecule.

General Formula

A formula showing the ratio of atoms in a family of compounds in terms of $n$, where $n$ is a varying whole number.

Displayed Formula

A graphical representation showing the spatial arrangement of all atoms and covalent bonds in a molecule.

Structural Formula

A chemical formula that shows enough structural information to make the arrangement clear while omitting most covalent bonds.

Homologous Series

A family of organic compounds that share similar features and chemical properties because they have the same functional group and general formula.

Functional Group

An atom or group of atoms bonded in a specific arrangement that determines the characteristic properties of a homologous series.

Isomerism

The phenomenon where compounds have the same molecular formula but different displayed or structural formulae.

Prefix "Meth-"

The organic nomenclature prefix indicating a parent carbon chain containing $1$ carbon atom.

Prefix "Eth-"

The organic nomenclature prefix indicating a parent carbon chain containing $2$ carbon atoms.

Prefix "Prop-"

The organic nomenclature prefix indicating a parent carbon chain containing $3$ carbon atoms.

Prefix "But-"

The organic nomenclature prefix indicating a parent carbon chain containing $4$ carbon atoms.

Prefix "Pent-"

The organic nomenclature prefix indicating a parent carbon chain containing $5$ carbon atoms.

Prefix "Hex-"

The organic nomenclature prefix indicating a parent carbon chain containing $6$ carbon atoms.

Suffix "-ane"

The organic nomenclature suffix used for saturated hydrocarbons in the alkane family.

Suffix "-ene"

The organic nomenclature suffix used for unsaturated hydrocarbons in the alkene family containing a $C=C$ bond.

Suffix "-anol"

The organic nomenclature suffix used for organic compounds in the alcohol family containing a hydroxyl group ($-OH$).

Suffix "-anoic acid"

The organic nomenclature suffix used for organic compounds in the carboxylic acid family containing a carboxyl group ($-COOH$).

Suffix "-amine"

The organic nomenclature suffix used for organic compounds containing an amine functional group ($-NH_2$).

Suffix "-yl -anoate"

The organic nomenclature naming format used for organic compounds in the ester family.

Monkeys Eat Peanut Butter

A mnemonic device used to remember the carbon chain prefix order for $1$ to $4$ carbon atoms: Meth-, Eth-, Prop-, But-.

Parent Chain

The longest continuous chain of carbon atoms in an organic molecule used to assign the prefix name.

Extension Bonds

Bonds drawn on either side of a polymer repeat unit extending outside the brackets to indicate continuation.

Continuation Bonds

Another name for extension bonds drawn through the brackets of a repeat unit to show ongoing polymer linkages.

Substitution Reaction

A reaction in which one functional group or atom in a molecule is replaced by another functional group or atom.

Addition Reaction

A reaction in which two or more molecules combine to form a single larger molecule with no other products.

Combustion Reaction

A reaction (burning) in which an organic substance reacts exothermicly with oxygen gas.

Complete Combustion

Oxidation of a fuel in an unlimited supply of oxygen, producing only carbon dioxide ($CO_2$) and water ($H_2O$).

Incomplete Combustion

Oxidation of a fuel in a limited supply of oxygen, producing carbon monoxide ($CO$) or soot ($C$) along with water ($H_2O$).

Thermal Decomposition

The reaction breaking down a chemical compound into simpler substances using high heat, such as in catalytic cracking.

Esterification

A condensation reaction between an alcohol and a carboxylic acid to form an ester and water.

Hydrolysis

A chemical reaction involving the addition of water to break down a polymer into its component monomer units.

Addition Polymerisation

The process where many unsaturated alkene monomers join across their $C=C$ double bonds to form a single long-chain polymer.

Condensation Polymerisation

The process where monomers with two functional groups combine, forming a polymer and eliminating a small molecule like water per linkage.

Crude Oil

A complex natural mixture consisting mainly of different hydrocarbon compounds.

Fraction (Crude Oil)

A group of hydrocarbons separated from crude oil that possess similar carbon chain lengths and boiling points.

Fractional Distillation

An industrial process used to separate crude oil into fractions based on differences in hydrocarbon boiling points.

Fractionating Column

A column used in fractional distillation containing a temperature gradient (hot at the base, cooler at the top).

Temperature Gradient

The temperature variation inside a fractionating column, being hottest at the bottom and coolest at the top.

Refinery Gas

A crude oil fraction containing $1$ to $4$ carbon hydrocarbons, boiling below $25\,^\circ\text{C}$, used for domestic heating and cooking.

Gasoline / Petrol

A crude oil fraction containing $4$ to $12$ carbon hydrocarbons, boiling between $40-100\,^\circ\text{C}$, used as fuel for cars.

Naphtha

A crude oil fraction containing hydrocarbons typically with $8$ to $12$ carbon atoms.

Kerosene / Paraffin

A crude oil fraction containing $12$ to $16$ carbon hydrocarbons, boiling between $150-240\,^\circ\text{C}$, used as jet fuel.

Diesel / Gas Oil

A crude oil fraction containing $14$ to $18$ carbon hydrocarbons, boiling between $220-300\,^\circ\text{C}$, used in diesel engines.

Fuel Oil

A crude oil fraction containing $19$ to $25$ carbon hydrocarbons, boiling between $250-320\,^\circ\text{C}$, used for ships and power stations.

Bitumen

A heavy crude oil fraction containing over $70$ carbon atoms, boiling above $350\,^\circ\text{C}$, used for surfacing roads and roofs.

Viscosity

A physical property measuring a liquid's resistance to flow; highly viscous liquids are thick and flow less easily.

Volatility

The tendency of a liquid substance to vaporise or convert into a gas at normal temperatures.

Trend in Boiling Point of Fractions

As carbon chain length increases down the fractionating column, boiling points increase due to stronger intermolecular forces.

Trend in Viscosity of Fractions

As carbon chain length increases down the fractionating column, the liquids become darker, thicker, and more viscous.

Trend in Colour of Fractions

As carbon chain length increases down the fractionating column, the fraction liquids become darker in colour.

Trend in Volatility of Fractions

As carbon chain length increases down the fractionating column, the fraction liquids become less volatile.

Fuel

Any combustible substance that undergoes a chemical reaction with oxygen to release heat energy in an exothermic reaction.

Exothermic Reaction

A reaction that releases heat energy to its surroundings, such as the combustion of hydrocarbon fuels.

Fossil Fuels

Non-renewable combustible materials formed over millions of years, including coal, crude oil, natural gas, oil shales, and tar sands.

Natural Gas

A non-renewable fossil fuel consisting mainly of methane ($CH_4$).

Carbon Monoxide ($CO$)

A poisonous, colourless, odourless, and tasteless gas produced during incomplete combustion of carbon-containing fuels.

Haemoglobin

The oxygen-transporting protein found inside red blood cells.

Carboxyhaemoglobin

A stable compound formed when carbon monoxide binds irreversibly to haemoglobin, preventing oxygen transport in the blood.

Carbon Monoxide Affinity Ratio

Haemoglobin binds to carbon monoxide approximately $200-250$ times more strongly than it binds to oxygen.

Symptoms of $CO$ Poisoning

Physiological symptoms resulting from oxygen deprivation, including headaches, dizziness, nausea, shortness of breath, loss of consciousness, and death.

Nitrogen Oxides ($NO_x$)

Pollutant gases formed when nitrogen and oxygen react under high pressure and temperature in car engines and blast furnaces.

Catalytic Converter

A exhaust system device fitted to vehicles that converts unburned hydrocarbons, $CO$, and nitrogen oxides into harmless gases.

Sulfur Impurities

Small amounts of elemental sulfur naturally present in fossil fuels that form sulfur dioxide when combusted.

Sulfur Dioxide ($SO_2$)

An acidic gas formed by burning sulfur-contaminated fossil fuels that reacts with atmospheric water droplets to cause acid rain.

Acid Rain

Precipitation made acidic by dissolved atmospheric pollutants such as sulfur dioxide ($SO_2$) and nitrogen dioxide ($NO_2$).

Ecological Impacts of Acid Rain

Environmental damages including limestone/metal corrosion, harm to aquatic life, crop pollution, water contamination, and respiratory irritation.

Unburned Hydrocarbons

Residual fuel molecules emitted in vehicle exhaust due to incomplete combustion.

Soot (Carbon Particulates)

Fine solid carbon particles produced during incomplete combustion of hydrocarbon fuels in oxygen-limited environments.

Photochemical Smog

Atmospheric pollution haze produced when nitrogen oxides and other pollutants react in sunlight.

Lightning Acid Rain Trigger

High-energy electrical discharges in the atmosphere that trigger nitrogen and oxygen to react, forming nitrogen oxides and nitric acid rain.

Cracking

An industrial thermal decomposition process breaking long-chain, low-demand alkanes into shorter, more useful alkanes and alkenes.

Catalytic Cracking Temperature

The temperature condition required for catalytic cracking, specified as $600-700\,^\circ\text{C}$.

Catalytic Cracking Catalyst

A hot powdered catalyst made of aluminium oxide ($Al_2O_3$) used in catalytic cracking.

Supply in Crude Oil Refining

The quantity of a specific crude oil fraction produced by fractional distillation.

Demand in Crude Oil Refining

The quantity of a specific crude oil fraction that consumers wish to buy.

Surplus Fractions

Heavy crude oil fractions (e.g. fuel oil and bitumen) where supply exceeds market demand, making them candidates for cracking.

Saturated Hydrocarbon

A hydrocarbon containing only single covalent carbon-carbon bonds ($C-C$).

Unsaturated Hydrocarbon

A hydrocarbon containing one or more double ($C=C$) or triple carbon-carbon covalent bonds.

Alkanes

A homologous series of saturated hydrocarbons with the general formula $C_n H_{2n+2}$.

General Formula of Alkanes

The elemental ratio formula $C_n H_{2n+2}$ describing all straight-chain alkanes.

Methane

The simplest alkane hydrocarbon with the molecular formula $CH_4$.

Ethane

A two-carbon alkane hydrocarbon with the molecular formula $C_2H_6$.

Propane

A three-carbon alkane hydrocarbon with the molecular formula $C_3H_8$.

Butane

A four-carbon alkane hydrocarbon with the molecular formula $C_4H_{10}$.

Pentane

A five-carbon alkane hydrocarbon with the molecular formula $C_5H_{12}$.

Methane Structural Formula

The structural notation representing methane as $CH_4$.

Ethane Structural Formula

The structural notation representing ethane as $CH_3CH_3$.

Propane Structural Formula

The structural notation representing propane as $CH_3CH_2CH_3$.

Butane Structural Formula

The structural notation representing butane as $CH_3CH_2CH_2CH_3$ or $CH_3(CH_2)_2CH_3$.

Pentane Structural Formula

The structural notation representing pentane as $CH_3CH_2CH_2CH_2CH_3$ or $CH_3(CH_2)_3CH_3$.

Alkane Halogenation

A substitution reaction between an alkane and a halogen in the presence of ultraviolet (UV) radiation.

UV Radiation Requirement

Ultraviolet light energy needed to initiate substitution reactions between alkanes and halogens.

Methane and Bromine Substitution

The photochemical substitution reaction: $CH_4 + Br_2 \rightarrow CH_3Br + HBr$.

Bromomethane

A halogenoalkane product with the formula $CH_3Br$ formed by halogenating methane with bromine.

Hydrogen Bromide

An inorganic gaseous byproduct with the formula $HBr$ produced during alkane bromination.

Halogenoalkanes (Haloalkanes)

A organic compound family formed when one or more hydrogen atoms in an alkane are replaced by halogen atoms.

Uses of Halogenoalkanes

Commercial applications of haloalkanes as solvents, refrigerants, propellants, and pharmaceuticals.

Reactivity of Alkanes

Alkanes are generally unreactive due to strong single bonds, but undergo combustion, cracking, and free-radical substitution.