PJM F322 - Chains, Rings & Resources Key Words

Functional Group
A group of atoms responsible for the characteristic reactions of a compound.
Homologous Series
A series of organic compounds having the same functional group but with each successive member differing by -CH2.
Structural Isomers
Structural isomers have the same molecular formula, but a different structural formula.
Chain Isomers
Compounds with the same molecular formula but with a different carbon chain length.
Positional Isomers
Compounds with the same molecular formula, but with a different POSITION of the functional group.
Functional Group Isomers
A compound with the same molecular formula, but with a different FUNCTIONAL group.
Empirical Formula
The simplest whole number ratio of atoms of each element in a compound e.g. CH2
Molecular formula
The actual number of atoms of each element in a molecule, e.g. C2H4.
Skeletal formula
The simplest organic formula, shown by removing the hydrogen atoms from alkyl chains to leave the carbon skeleton.
E/Z isomerism
A type of stereoisomerism. Double bond stops rotation and different groups are attached to the carbons in the double bond
Homolytic fission
When a covalent bond breaks giving an electron to each atom creating 2 radicals
Hetrolyic fission
When a covalent bond breaks and give both electrons to 1 atom forming 1 positive and 1 negative ion
A species with an unpaired electron
An electron pair donor
An electron pair acceptor
Nucleophile substitution
When a nucleophile replaces a halogen
Free radical substitution
When a halogen replaces a H in a multi-step reaction.
Electrophilic addition
When a species adds across a double bond
Pi bond
Formed by the sideways overlap of adjacent p orbitals
A large chain molecule formed from repeating monomer units.
Atom economy
(Mr of desired product/Mr of all products) x100
Activation energy
Minimum energy requires to start a chemical reaction.
Standard enthalpy change of reaction
Is the enthalpy change that accompanies a reaction of 1 mol of reactants under standard conditions and in standard states.
Standard enthalpy of formation
The enthalpy change that takes place when 1 mole of a compounds is formed from its elements in their standard stated under standard conditions.
Standard enthalpy chemise of combustion
The enthalpy change that takes place when one mole of substance in its standard state reacts completely with oxygen under standard conditions.
Alkyl group
An alkane with a hydrogen removed e.g. -CH3 often shown as R.
Avagadros constant
The number of atoms in a mole of substance.
The breaking down of long changed alkanes to form a mixture of smaller alkanes and alkenes.
Boltzmann distribution
The distribution of energies of molecules at a particular temperature.
Fractional distillation
The separation of components in a liquid mixture into fractions which differ in boiling points
Enthalpy profile diagram
A diagram that shows the difference between the e enthalpies of the reactant and products of a reaction.
Le Chatelier's Principle
When a system in dynamic equilibrium is subjected to a change, the position of equilibrium will shift to minimise the change.
A substance that increases the rate of a chemical reaction, without being used up in the process.
A catalyst used to crack large alkane molecules.
A small molecule that combines with other monomers to form a polymer.
Specific heart capacity
The energy required to raise the temperature of 1g of a substance by one degree Celsius.
Standard conditions
A pressure of 100kPa (1 atm), a concentration of 1 mol per dm3 and a temperature of 298K.
Curly Arrow
A symbol used in a reaction mechanisms to show the movement of electrons in the formation of a covalent bond.
An elimination reaction in which water is removed from a saturated molecule to make an unsaturated molecule
Dynamic Equilibrium
The equilibrium that exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction
The reaction of an alcohol with a carboxylic acid to produce an ester and water
General Formula
The simplest algebraic formula of a member of a homologous series.
Greenhouse effect
The process in which the adsorption and subsequent emission of infrared radiation by atmospheric gases warms the lower atmosphere and the planet's surface
Percentage Yield
= actual amount (in mol) of product DIVIDED by theoretical amount (in mol) of product MULTIPLIED x 100
The molar relationship between the relative quantities of substances taking part in a reaction
The two steps in a radical substitution reaction where new radicals are formed.
The first step in a radical substitution in which the free radicals are generated by ultraviolet radiation
The step at the end of a radical substitution when two radicals combine to form a molecule
Unsatutated hydrocarbon
A hydrocarbon containing carbon-carbon double bonds.
Saturated hydrocarbon
A hydrocarbon that contains carbon-carbon single bonds.
Compounds with the same structural formula, but with a different arrangement of the atoms in space.