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A Level Chemistry OCR A (2022) > A Level Chemistry Definitions > Flashcards

A Level Chemistry Definitions Flashcards

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1
Q

acid

A

A species that releases H+ ions in aqueous solution

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2
Q

acid dissociation constant Ka

A

The equilibrium constant that shows the extent of dissociation of a weak acid. For a weak acid HA(aq),

Ka = [H+(aq)][A-(AQ)]/[HA(aq)]

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3
Q

acid-base pair

A

A pair of two species that transform into each other by gain or loss of a proton

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4
Q

activation energy

A

The minimum energy required to start a reaction by the breaking of bonds

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5
Q

actual yield

A

The amount of product obtained from a reaction

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6
Q

addition polymerisation

A

Formation of a very long molecular chain, by repeating addition reactions of many unsaturated alkene molecules (monomers)

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7
Q

addition reaction

A

A reaction in which two reactants join together to form one product

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8
Q

adsorption

A

The process that occurs when a gas or liquid or solute is held to the surface of a solid

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9
Q

alicyclic

A

Containing carbon atoms joined together in a ring that is not aromatic

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10
Q

aliphatic

A

Containing carbon atoms joined together in straight or branched chains

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11
Q

alkali

A

A type of base that dissolves in water forming hydroxide ions, OH-(aq) ions

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12
Q

alkanes

A

The hydrocarbon homologous series with single carbon-to-carbon bonds and the general formula:

CnH2n+2

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13
Q

alkenes

A

The hydrocarbon homologous series with at least one double carbon-to-carbon bonds and the general formula:

CnH2n

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14
Q

alkyl group

A

A side chain formed by removing a hydrogen atom removed from an alkane parent chain, for example, CH3, C2H5; any alkyl group is often shown as R.

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15
Q

alkynes

A

The hydrocarbon homologous series with at least one triple carbon-to-carbon bonds and the general formula:

CnH2n-2

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16
Q

amount of substance

A

The quantity whose unit of the mole, used as a means of counting any species such as atoms, ions and molecules.

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17
Q

anhydrous

A

Containing no water molecules

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18
Q

anion

A

A negatively charged ion with more electrons than protons

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19
Q

aromatic

A

Containing one or more benzene rings

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20
Q

atom economy

A

(Sum of molar masses of desired products)/(sum of molar masses of all products)

A ~ 100%

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21
Q

atomic (proton) number

A

The number of protons in the nucleus of an atom

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22
Q

atomic orbital

A

A region around the nucleus that can hold up to two electrons, with opposite spins

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23
Q

average bond enthalpy

A

The average enthalpy change that takes place when breaking by homolytic fission 1 mol of a given type of bond in the molecules of a gaseous species

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24
Q

Avogadro constant NA

A

The number of atoms per mole of the carbon-12 isotope (6.02 x10^23 mol^-1)

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25
Q

base

A

A compound that neutralises an acid to form a salt

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26
Q

binary compound

A

A compound containing two elements only

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27
Q

bond angle

A

The angle between two bonds at an atom

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28
Q

bond dissociation enthalpy

A

The enthalpy change that takes place when breaking by homolytic fission 1 mol of a given bond in the molecules of a gaseous species

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29
Q

bonded pair

A

A pair of electrons shared between two atoms to make a covalent bond

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30
Q

Bronsted-Lowry acid

A

A species that is a proton, H+, donor

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31
Q

Bronsted-Lowry base

A

A species that is a proton, H+, acceptor

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32
Q

buffer solution

A

A system that minimises pH changes on addition of small amounts of an acid or a base

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33
Q

carbocation

A

An ion that contains a positively charged carbon atom

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34
Q

catalyst

A

A substance that increases the rate of a chemical reaction without being used up in the process; a catalyst provides an alternative route for the reaction with a lower activation energy

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35
Q

cation

A

A positively charged ion with fewer electrons than protons

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36
Q

chain reaction

A

A reaction in which the propagation steps release new radicals that continue the reaction

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37
Q

chemical shift δ

A

A scale, in ppm, that compares the frequency of an NMR absorption with the frequency of the reference TMS at δ = 0 ppm

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38
Q

chiral carbon

A

A carbon atom attached to four different atoms or groups of atoms

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39
Q

chromatogram

A

A visible record showing the result of separation of the components of a mixture by chromatography

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40
Q

cis-trans isomerism

A

A special type of E/Z isomerism in which there are two non-hydrogen groups and two hydrogen atoms around the C=C double bond: the cis isomer (Z isomer) has H atoms on each carbon on the same side; the trans isomer (E isomer) has H atoms on each carbon on different sides

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41
Q

closed system

A

A system isolated from its surroundings

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42
Q

collision theory

A

Two reacting particles must collide for a reaction to occur, and must be in the correct orientation and have sufficient energy to overcome the activation energy of the reaction

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43
Q

complex ion

A

A transition metal ion bonded to ligands by coordinate bonds (dative covalent bonds)

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44
Q

concentration

A

The amount of solute, in moles, dissolved in 1 dm^3 (1000cm^3) of solution

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45
Q

condensation reaction

A

A reaction in which two small molecules react together to form a larger molecule with elimination of a small molecule such as water

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46
Q

conjugate acid

A

A species that releases a proton to form a conjugate base

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47
Q

conjugate base

A

A species that accepts a proton to form a conjugate acid

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48
Q

coordinate bond

A

A shared pair of electrons in which the bonded pair has been provided by one of the bonding atoms only; also called a dative covalent bond

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49
Q

coordination number

A

The total number of coordinate bonds formed between a central metal ion and its ligands

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50
Q

covalent bond

A

The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms

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51
Q

dative covalent

A

A shared pair of electrons in which the bonded pair has been provided by one of the bonding atoms only; also called a coordinate bond

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52
Q

dehydration

A

An elimination reaction in which water is removed from a saturated molecule to make an unsaturated molecule

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53
Q

delocalised electrons

A

Electrons that are shared between more than two atoms

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54
Q

desorption

A

Release of an adsorbed substance from a surface

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55
Q

dipole

A

A separation in electrical charge so that one atom of a polar covalent bond, or one end of a polar molecule, has a small positive charge δ+ and the other has a small negative charge δ-

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56
Q

displacement reaction

A

A reaction in which a more reactive element displaces a less reactive element from an aqueous solution of its ions

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57
Q

displayed formula

A

A formula showing the relative positioning of all the atoms in a molecule and the bonds between them

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58
Q

disproportionation

A

A redox reaction in which the same element is both oxidised and reduced

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59
Q

dynamic equilibrium

A

The equilibrium that exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction and concentrations do not change

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60
Q

E/Z isomerism

A

A type of stereoisomerism in which different groups attached to each carbon of a C=C double bond may be arranged differently in space because of the restricted rotation of the C=C bond

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61
Q

electron configuration

A

A shorthand representation that shows how electrons occupy sub-shells in an atom

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62
Q

electronegativity

A

A measure of the attraction of a bonded atom for the pair of electrons in a covalent bond

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63
Q

electrophile

A

An atom (or group of atoms) which is attracted to an electron-rich centre or atom, where it accepts a pair of electrons to form a new covalent bond

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64
Q

electrophilic addition

A

An addition reaction in which the first step is attack by an electrophile on a region of high electron density

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65
Q

electrophilic substitution

A

A type of substitution reaction in which an electrophile is attracted to an electron-rich centre or atom, where it accepts a pair of electrons to form a new covalent bond

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66
Q

elimination reaction

A

The removal of a molecule from a saturated molecule to make an unsaturated molecule

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67
Q

empirical formula

A

The formula that shows the simplest whole-number ratio of atoms of each element present in a compound

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68
Q

enantiomers

A

Stereoisomers that are non-superimposable mirror images of each other; also called optical isomers

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69
Q

end point

A

The point in a titration where the indicator changes colour; the end point indicates when the reaction is just complete

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70
Q

endothermic reaction

A

A reaction in which the enthalpy of the products is greater than the enthalpy of the reactants, resulting in heat being taken in from the surroundings (∆H +ve).

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71
Q

enthalpy H

A

The heat content that is stored in a chemical system

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72
Q

enthalpy change ΔH

A

The difference between the enthalpy of the products and the enthalpy of the reactants

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73
Q

enthalpy cycle

A

A diagram showing alternative routes between reactants and products which allows the indirect determination of an enthalpy change from other known enthalpy changes using Hess’ law

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74
Q

enthalpy profile diagram

A

A diagram for a reaction to compare the enthalpy of the reactants with the enthalpy of the products

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75
Q

entropy

A

The used for the dispersal of energy and disorder within the chemicals making up the chemical system

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76
Q

equilibrium constant Kc

A

A measure of the position of equilibrium; the magnitude of an equilibrium constant indicates whether there are more reactants or more products in an equilibrium system

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77
Q

equivalence point

A

The point in a titration at which the volume of one solution has reacted exactly with the volume of the second solution

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78
Q

esterification

A

A reaction in which a carboxylic acid reacts with an alcohol to form an ester and water

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79
Q

exothermic reaction

A

A reaction in which the enthalpy of the products is smaller than the enthalpy of the reactants, resulting in heat loss to the surroundings (∆H -ve)

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80
Q

fingerprint region

A

An area of an infrared spectrum below 1500cm^-1 that gives a characteristic pattern for different compounds

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81
Q

first electron affinity

A

The enthalpy change that takes place when one electron is added to each atom in one mole of gaseous atoms to form one mole of gaseous 1- ions

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82
Q

first ionisation energy

A

The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions

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83
Q

fractional distillation

A

The separation of components in a liquid mixture by their different boiling points into fractions with different compositions

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84
Q

fragment ions

A

Ions formed from the breakdown of the molecular ion in a mass spectrometer

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85
Q

fragmentation

A

The process in mass spectrometry that causes a positive ion to split into smaller pieces, one of which is a positive fragment ion

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86
Q

free energy change ∆G

A

The balance between enthalpy, entropy and temperature for a process

∆G=∆H-T∆S

A process is feasible when ∆G<0

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87
Q

functional group

A

The part of the organic molecule responsible for its chemical reactions

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88
Q

general formula

A

The simplest algebraic formula of a member of a homologous series. For example, the general formula of the alkanes is CnH2n+2

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89
Q

giant covalent lattice

A

A three-dimensional structure of atoms, bonded together by strong covalent bonds

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90
Q

giant ionic lattice

A

A three-dimensional structure of oppositely charged ions, bonded together by strong ionic bonds

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91
Q

giant metallic lattice

A

A three-dimensional structure of positive ions and delocalised electrons, bonded together by strong metallic bonds

92
Q

group

A

A vertical column in the periodic table. Elements in a group have similar chemical properties and their atoms have the same number of outer shell electrons

93
Q

half-life

A

The time taken for the concentration of a reactant to decrease by half

94
Q

Hess’ law

A

If a reaction can take place by more than one route and the initial and final conditions are the same, the total enthalpy change is the same for each route

95
Q

heterogeneous catalysis

A

A reaction in which the catalyst has a different physical state from the reactants; frequently, reactants are gases whilst the catalyst is a solid

96
Q

heterogeneous equilibrium

A

An equilibrium in which the species making up the reactants and products are in different physical states

97
Q

heterolytic fission

A

The breaking of a covalent bond forming a cation (positive ion) and an anion (negative ion)

98
Q

homogeneous catalysis

A

A reaction in which the catalyst and reactants are in the same physical state, which is most frequently the aqueous or gaseous state

99
Q

homogeneous equilibrium

A

An equilibrium in which all the species making up the reactants and products are in the same physical state

100
Q

homologous series

A

A series of organic compounds with the same functional group but with each successive member differing by CH2

101
Q

homolytic fission

A

The breaking of a covalent bond with one of the bonded electrons going to each atom, forming two radicals

102
Q

hydrated

A

A crystalline compound containing water molecules

103
Q

hydrocarbon

A

A compound composed of only carbon and hydrogen

104
Q

hydrogen bond

A

A strong dipole-dipole attraction between an electron-deficient hydrogen atom of -NH, -OH, or HF on one molecule and a lone pair of electrons on a highly electronegative atom containing N, O or F on a different molecule

105
Q

hydrolysis

A

A reaction with water that breaks a chemical compound into two compounds, the H and OH in a water molecule becomes incorporated into the two compounds

106
Q

induced dipole-dipole interaction

A

Attractive forces between induced dipoles in different molecules - also called London Forces

107
Q

infrared spectroscopy

A

An instrumentation method of analysis that identifies bonds from absorption of the infrared radiation of different wavelengths

108
Q

initial rate of reaction

A

The change in concentration of a reactant or product per unit time at the start of the reaction when t=0

109
Q

initiation

A

The first stage in a radical reaction in which radicals start when a covalent bond is broken by homolytic fission of a covalent bond

110
Q

intermediate

A

A species formed during a reaction that reacts further and is not present in the final products

111
Q

intermolecular force

A

An attractive force between molecules. Intermolecular forces can be London forces, permanent dipole-dipole interactions or hydrogen bonding

112
Q

ion

A

A positively or negatively charged atom or a (covalently bonded) group of atoms (a polyatomic ion), where the number of electrons is different from the number of protons

113
Q

ionic bonding

A

The electrostatic attraction between oppositely charged ions

114
Q

ionic product of water Kw

A

The product of the ions formed in the partial dissociation of water, given by Kw = [H+(aq)] [OH-(aq)]

115
Q

isotopes

A

Atoms of the same element with different numbers of neutrons and different masses

116
Q

lattice enthalpy

A

The enthalpy change that accompanies the formation of one mole of an ionic compound from its gaseous ions under standard conditions

117
Q

Le Chatelier’s Principle

A

When a system in dynamic equilibrium is subjected to an external change, the system readjusts itself to minimise the effect of the change and to restore equilibrium

118
Q

ligand

A

A molecule or ion that can donate a pair of electrons to the transition metal ion

119
Q

ligand substitution

A

A reaction in which one or more ligands in a complex ion are replaced by different ligands

120
Q

limiting reagent

A

The reactant that is not in excess, which will be used up first and stop the reaction

121
Q

lone pair

A

An outer shell pair of electrons that is not involved in chemical bonding

122
Q

mass number

A

The sum of the number of protons and neutrons in the nucleus - also known as nucleon number

123
Q

metallic bond

A

The electrostatic attraction between positive metal ions and delocalised electrons

124
Q

mobile phase

A

The phase that moves in chromatography

125
Q

molar gas volume Vm

A

The volume per mole of gas molecules at a stated temperature and pressure

126
Q

molar mass M

A

The mass mole of a substance in units of g mol-1

127
Q

mole

A

The amount of any substance containing as many elementary particles as there are carbon atoms in exactly 12g of the carbon-12 isotope, that is, 6.02 x10^23 particles

128
Q

molecular formula

A

A formula that shows the number and type of atoms of each element present in a molecule

129
Q

molecular ion

A

The positive ion formed in mass spectrometry when a molecule loses an electron

130
Q

molecule

A

The smallest part of a covalent compound that can exist while retaining its chemical identity, consisting of two or more atoms covalently bonded together

131
Q

monomer

A

A small molecule that combines with many other monomers to form a polymer

132
Q

neutralisation

A

A chemical reaction in which an acid and a base react together to produce a salt and water

133
Q

nomenclature

A

A system of naming compounds

134
Q

non-polar

A

With no charge separation across a bond or in a molecule

135
Q

nucleophile

A

An atom (or group of atoms) that is attracted to an electron-deficient centre or atom, where it donates a pair of electrons to form a new covalent bond

136
Q

nucleophilic substitution

A

A reaction in which a nucleophile is attracted to an electron-deficient carbon atom, and replaces an atom or group of atoms on the carbon atom

137
Q

optical isomers

A

Stereoisomers that are non-superimposable mirror images of each other; also called ‘enantiomers’

138
Q

order

A

The power to which the concentration of a reactant is raised in the rate equation

139
Q

overall order

A

The sum of the individual orders of reactants in the rate equation: m + n

140
Q

oxidation

A

Loss of electrons or an increase in oxidation number

141
Q

oxidation number

A

A measure of the number of electrons that an atom uses to bond with atoms of another element. Oxidation numbers are derived from a set of rules

142
Q

oxidation state

A

The oxidation number

143
Q

oxidising agent

A

A reagent that oxidises (takes electrons from) another species

144
Q

π-bond

A

A bond formed by the sideways overlap of two p-orbitals, with the electron density above and the plane of the bonding atoms

145
Q

partial dissociation

A

The splitting of some of a species in solution into aqueous ions

146
Q

Pauling electronegativity value

A

A value assigned as a measure of the relative attraction of a bonded atom for the pair of electrons in a covalent bond

147
Q

percentage yield

A

% yield = (actual amount, in mol, of product) / (theoretical amount, in mol, of product) x 100

148
Q

period

A

A horizontal row of elements in the periodic table. Elements show trend in properties across a period

149
Q

periodicity

A

A repeating trend in properties of the elements across each period of the periodic table

150
Q

permanent dipole

A

A small charge difference that does not change across a bond, with δ+ and δ- partial changes on the bonded atoms: the result of the bonded atoms having different electronegativities

151
Q

Permanent dipole-dipole interaction

A

An attractive force between permanent dipoles in neighbouring polar molecules

152
Q

pH

A

The expression:

pH = -log[H+(aq)]

153
Q

polar (molecule)

A

With δ+ and δ- charges at different ends of the molecule

154
Q

polar covalent bond

A

A bond with a permanent dipole, having δ+ and δ- partial changes on the bonded atoms

155
Q

polar molecule

A

A molecule with an overall dipole, having taken into account any dipoles across bonds and the shape of the molecule

156
Q

polyatomic ion

A

An ion containing more than one atom

157
Q

polymer

A

A large molecule formed from many thousands of repeat units of smaller molecules known as monomers

158
Q

position of equilibrium

A

The relative quantities of reactants and products, indicating the extent of a reversible reaction at equilibrium

159
Q

precipitation reaction

A

The formation of a solid from a solution during a chemical reaction. Precipitates are often formed when two aqueous solutions are mixed together

160
Q

primary

A

On a carbon atom at the end of a chain

161
Q

primary alcohol

A

An alcohol in which the OH group is attached to a carbon atom that is attached to two or three hydrogen atoms

162
Q

principal quantum number n

A

A number representing the relative overall energy of each orbital, which increases with distance from the nucleus. The sets of orbitals with the same n-value are referred to as electron shells or energy levels

163
Q

propagation

A

The steps that continue a free radical reaction, in which a radical reacts with a reactant molecule to form a new molecule and another radical, causing a chain reaction

164
Q

proton number

A

The number of protons in the nucleus of an atom; also known as atomic number

165
Q

radical

A

A species with an unpaired electron

166
Q

rate constant k

A

The constant that links the rate of reaction with the concentrations of the reactants raised to the powers of their orders in the rate equation

167
Q

rate equation

A

For a reaction: A + B → C with orders m for A and n for B, the rate equation is given by:

rate = k[A]^m[B]^n

168
Q

rate-determining step

A

The slowest step in the reaction mechanism of a multi-step reaction

169
Q

reaction mechanism

A

The sequence of bond breaking and bond-forming steps that shows the path taken by electrons during a reaction

170
Q

redox reaction

A

A reaction involving reduction and oxidation

171
Q

reducing agent

A

A reagent that reduces (adds electrons to) another species

172
Q

reduction

A

Gain of electrons or a decrease in oxidation number

173
Q

reflux

A

The continual boiling and condensing of a reaction mixture back to the original container to ensure that the reaction takes place without the contents of the flask boiling dry

174
Q

relative atomic mass Ar

A

The weighted mean mass of an atom of an element compared with one-twelfth of the mass of an atom of carbon-12

175
Q

relative formula mass

A

The weighted mean mass of the formula unit of a compound compared with one twelfth of the mass of an atom of carbon-12

176
Q

relative isotopic mass

A

The mass of an atom of an isotope compared with one twelfth of the mass of an atom of carbon-12

177
Q

relative molecular mass

A

The weighted mean mass of a molecule of a compound compared with one twelfth of the mass of an atom of carbon-12

178
Q

repeat unit

A

A specific arrangement of atoms that occurs in the structure over and over again. Repeat units are included in brackets, outside of which is the symbol n

179
Q

retention time

A

In gas chromatography, it is the time for a component to pass from the column inlet to the detector

180
Q

reversible reaction

A

A reaction that takes place in both forward and reverse directions

181
Q

Rf value

A

Rf = distance moved by component / distance moved by solvent

182
Q

σ bond

A

A bond formed by the overlap of one orbital from each bonding atom, consisting of two electrons and with the electron density centred around a line directly between the nuclei of the two atoms

183
Q

salt

A

The product of a reaction in which the H- ions from the acid are replaced by metal or ammonium ions

184
Q

saturated

A

Containing single bonds only

185
Q

saturated hydrocarbon

A

A hydrocarbon with single bonds only

186
Q

second electron affinity

A

The enthalpy change that takes place when one electron is added to each ion in one mole of gaseous 1- ions to form one mole of gaseous 2- ions

187
Q

second ionisation energy

A

The energy needed to remove 1 electron from each ion in 1 mole of gaseous 1+ ions to form 1 mole of gaseous 2+ ions

188
Q

secondary

A

On a carbon atom to which two carbon chains are attached

189
Q

secondary alcohol

A

An alcohol in which the -OH group is attached to a carbon atom that is attached to two carbon chains and one hydrogen atom

190
Q

shell

A

A group of atomic orbitals with the same principal quantum number, n. Also known as a main energy level

191
Q

shielding effect

A

The repulsion between electrons in different inner shells. Shielding reduces the net attractive force between the positive nucleus on the outer shell electrons

192
Q

simple molecular lattice

A

A three-dimensional structure of molecules, bonded together by weak intermolecular forces

193
Q

skeletal formula

A

A simplified organic formula, with hydrogen atoms removed from alkyl chains, leaving just a carbon skeleton and associated functional groups

194
Q

specific heat capacity c

A

The energy required to raise the temperature of 1 g of a substance by 1 °C

195
Q

spectator ions

A

Ions that are present but take no part in a chemical reaction

196
Q

spin-spin coupling

A

In an NMR spectrum, the interaction between spin states of non-equivalent nuclei that results in the splitting of a signal

197
Q

standard conditions

A

A pressure of 100 kPa (1 atmosphere), a stated temperature, usually 298 K (25 °C), and a concentration of 1 mol dm^-3 (for reactions with aqueous solutions)

198
Q

standard electrode potential E

A

The e.m.f of a half-cell compared with a standard hydrogen half-cell, measured at 298 K with solution concentrations of 1 mol dm^-3 and a gas pressure of 100kPa

199
Q

standard enthalpy change of atomisation

A

The enthalpy change that takes place when one mole of gaseous atoms forms from the element it its standard state

200
Q

standard enthalpy change of combustion ∆cH

A

The enthalpy change that takes place when one mole of a substance reacts completely with oxygen under standard conditions, with all reactants and products in their standard states

201
Q

standard enthalpy change of formation ∆fH

A

The enthalpy change that takes place when one mole of a compound is formed from its constituent elements in their standard states under standard conditions

202
Q

standard enthalpy change of hydration

A

The enthalpy change that takes place when one mole of isolated gaseous ions is dissolved in water forming one mole of aqueous ions under standard conditions

203
Q

standard enthalpy change of neutralisation ∆neutH

A

The enthalpy change that accompanies the reaction of an acid by a base to form one mole of H2O (l), under standard conditions, with all reactants and products in their standard states

204
Q

standard enthalpy change of reaction ∆rH

A

The enthalpy change that accompanies a reaction in the molar quantities expressed in a chemical equation under standard conditions, with all reactants and products in their standard states

205
Q

standard enthalpy change of solution

A

The enthalpy change that takes place when one mole of a compound is completely dissolved in water under standard conditions

206
Q

standard solution

A

A solution of known concentration

207
Q

standard state

A

The physical state of a substance under standard conditions of 100 kPa and a stated temperature (usually 298 K)

208
Q

stationary phase

A

The phase that does not move in chromatography

209
Q

stereoisomers

A

Compounds with the same structural formula but with a different arrangement of the atoms in space

210
Q

stoichiometry

A

The ratio of the amount, in moles, of each substance in a chemical equation (essentially the ratio of the balancing numbers)

211
Q

strong acid

A

An acid that dissociates completely in solution

212
Q

structural formula

A

A formula showing the minimal detail for the arrangement of atoms in a molecule

213
Q

structural isomers

A

Molecules with the same molecular formula but with different structural formulae

214
Q

sub-shell

A

A group of orbitals of the same type within a shell

215
Q

substitution reaction

A

A reaction in which an atom or group of atoms is replaced with a different atom or group of atoms

216
Q

surroundings

A

Everything that is not the chemical system

217
Q

system

A

The chemicals involved in the reaction

218
Q

termination

A

The step at the end of a radical substitution when two radicals combine to form a molecule

219
Q

tertiary alcohol

A

An alcohol in which the hydroxyl (-OH) group is attached to a carbon that is in turn attached to three other carbon atoms and no hydrogen atoms

220
Q

theoretical yield

A

The yield resulting from complete conversion of reactants into products

221
Q

thermal decomposition

A

The breaking up of a chemical substance with heat into at least two chemical substances

222
Q

titre

A

The volume added from the burette when the volume of one solution has exactly reacted with the other solution

223
Q

transition element

A

A d-block element which forms an ion with an incomplete d-sub-shell

224
Q

unsaturated

A

Containing a multiple carbon-carbon bond

225
Q

volatility

A

The ease at which a liquid turns into a gas. Volatility increases as boiling point decreases

226
Q

water of crystallisation

A

Water molecules that are bonded into a crystalline structure of a compound

227
Q

weak acid

A

An acid that dissociates only partially in solution

A Level Chemistry OCR A (2022) (10 decks)

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