Key term
Eduqas A-Level Chemistry A410QS
Formulae and Equations
Basic Ideas About Atoms
Topic overviewRadioactive decay and nuclear equationsBehaviour of α, β and γ radiationHalf-life and radioactive decay calculationsRadiation hazards and the uses of radioisotopesIonisation energy and its variation between elementsSuccessive ionisation energies and electronic structureOrbitals and electron configurations of elements 1 to 36Emission and absorption spectraThe hydrogen spectrum, E = hf and the convergence limit
Chemical Calculations
Topic overviewRelative atomic, isotopic, formula and molecular massPrinciples of the mass spectrometerMass spectra, isotopic abundance and relative atomic massEmpirical and molecular formulaeThe mole, the Avogadro constant and molar massMoles, grams and numbers of particlesConcentration and solubilityMolar volume and gas volume correctionsThe ideal gas equationStoichiometry and reacting quantitiesAcid-base titration calculationsAtom economy, percentage yield and percentage error
Bonding
Solid Structures
The Periodic Table
Topic overviewArrangement of the elements and the s-, p- and d-blocksOxidation and reduction as electron transferTrends across periods and down groupsReactions of Group 2 elements with oxygen, water and steamReactions of the aqueous cations Mg²⁺, Ca²⁺ and Ba²⁺Flame coloursReactivity of Group 1 and Group 2 metalsThermal stability of the Group 2 carbonates and hydroxidesSolubility of the Group 2 hydroxides and sulfatesBasic character of the Group 1 and Group 2 oxides and hydroxidesVolatility of the halogens and their reactions with metalsOxidising power, displacement reactions and the silver nitrate testWater treatment, salt preparation and gravimetric analysis
Simple Equilibria and Acid-Base Reactions
Thermochemistry
Rates of Reaction
The Wider Impact of Chemistry
Organic Compounds
Hydrocarbons
Topic overviewAlkanes and the sigma-bonded frameworkCombustion of alkanes and the use of fossil fuelsFree radical substitution and the photochlorination of alkanesAlkenes and the reactivity of the C=C bondE–Z isomerismElectrophilic addition of bromine to alkenesTests for alkenesMarkovnikov addition of hydrogen bromide and carbocation stabilityCatalytic hydrogenation of alkenesAddition polymerisation
Halogenoalkanes
Topic overviewNucleophilic substitution of primary halogenoalkanesElimination reactions forming alkenesBond polarity, bond enthalpy and the ease of substitutionThe silver nitrate test for halogenoalkanesUses of halogenoalkanes and the regulation of their useCFCs and their effect in the upper atmosphereHeating under reflux
Alcohols and Carboxylic Acids
Topic overviewIndustrial preparation of ethanol from etheneFermentation and the distillation of ethanolBiofuels and the issues they raiseClassifying alcohols as primary, secondary and tertiaryDehydration of alcohols to alkenesOxidation of primary alcohols to aldehydes and carboxylic acidsOxidation of secondary alcohols to ketonesThe dichromate(VI) test for alcoholsCarboxylic acids and the sodium hydrogencarbonate testReactions of carboxylic acids with bases, carbonates and hydrogencarbonatesEsterification and separation by distillation
Instrumental Analysis
Redox and Standard Electrode Potential
Redox Reactions
Chemistry of the P-Block
Topic overviewAmphoteric behaviour of aluminium and leadThe inert pair effect in Groups 3, 4 and 5Electron-deficient compounds and expanded octetsAl₂Cl₆ and donor-acceptor compoundsHexagonal and cubic boron nitrideStability of oxidation states II and IV in Group 4Carbon dioxide and lead(II) oxideBonding in the Group 4 chloridesHydrolysis of the Group 4 chloridesReactions of aqueous lead(II) ionsChlorine with cold and warm aqueous sodium hydroxideBleaching and bactericidal action of chlorine and chlorate(I)Sodium halides with concentrated sulfuric acid
Chemistry of the D-Block Transition Metals
Topic overviewOxidation states of the d-block elementsImportant oxidation states and the colours of aqueous ionsBonding in tetrahedral and octahedral complexesThe origin of colour and the splitting of d-orbitalsLigand exchange and change of coordination numberColours and formulae of copper and cobalt complex ionsHeterogeneous and homogeneous catalysisNickel in hydrogenation and iron in the Haber processVanadium(V) oxide and manganese(IV) oxide as catalystsReactions of Cr³⁺, Fe²⁺, Fe³⁺ and Cu²⁺ with excess aqueous hydroxide
Chemical Kinetics
Enthalpy Changes for Solids and Solutions
Entropy and Feasibility of Reactions
Equilibrium Constants
Acid-Base Equilibria
Topic overviewThe Lowry–Brønsted theory and conjugate pairsStrong and weak acids and the dissociation constant KaThe ionic product of water, KwpH of strong acids and strong basespH of weak acids from Ka and pKaTitration curvesHow buffer solutions workBuffer calculationsBuffers in living systems and industrySalt hydrolysis and the choice of indicator
Stereoisomerism
Aromaticity
Alcohols and Phenols
Aldehydes and Ketones
Topic overviewPreparing aldehydes and ketones by oxidation of alcoholsDistinguishing aldehydes and ketones with Tollens’ reagent and Fehling’s solutionReduction of aldehydes and ketones using NaBH₄Nucleophilic addition of HCN to aldehydes and ketonesReaction with 2,4-dinitrophenylhydrazineThe triiodomethane (iodoform) test
Carboxylic Acids and Their Derivatives
Topic overviewRelative acidity of carboxylic acids, phenols, alcohols and waterPreparing carboxylic acids by oxidationReduction and decarboxylation of carboxylic acidsAcid chlorides and their reactionsEsters and their hydrolysisAmides and their hydrolysisNitriles from carboxylic acids and halogenoalkanesHydroxynitriles, hydrolysis and reduction of nitriles
Amines
Amino Acids, Peptides and Proteins
Organic Synthesis and Analysis
Topic overviewPlanning a multi-step synthesisChoosing between alternative routesManipulation and separation techniquesPurification and melting temperatureAddition and condensation polymerisationPolyesters and polyamidesHigh resolution proton NMRCombining spectra to elucidate a structureInterpreting chromatographic dataGas chromatography and HPLC
Specified Practical Work
Topic overviewGravimetric analysis and qualitative analysis of unknown solutionsStandard solutions, standardising an acid and preparing a soluble saltBack titration and double titrationDetermining enthalpy changes by calorimetryFollowing a rate by gas collection, the iodine clock and reaction orderElectrochemical cells, redox titration and the estimation of copperDetermining an equilibrium constant and following a titration with a pH probeHydrolysis of 1-bromobutane and the preparation of an esterOrganic synthesis, purification and identification
Practical Skills and Techniques
Topic overviewChoosing apparatus and recording measurementsVolumetric technique with pipette, burette and volumetric flaskTitration procedure and the choice of indicatorHeating, heating under reflux and distillationFiltration, purification and qualitative testingMelting temperature, chromatography and electrochemical cellsVariables, errors and risk in evaluating a method
Mathematical Skills in Chemistry
Topic overviewStandard form, units and significant figuresRatios, fractions and percentagesChanging the subject and substituting valuesLogarithms, pH and pKaExponentials, the Arrhenius equation and rateGraphs, gradients and interceptsTangents and rates of changeArea under a curveUncertainty and combining errorsThe gas equation and equilibrium expressions
Halogenoalkanes
- 7 subtopics
- 21 things to know
- Components 1 and 2
What Halogenoalkanes covers
Halogenoalkanes is examined in Components 1 and 2, since the Core Ideas are examined on both written papers, and drawn on again in Component 3. It covers nucleophilic substitution of primary halogenoalkanes, elimination reactions forming alkenes, bond polarity, bond enthalpy and the ease of substitution, the silver nitrate test for halogenoalkanes, uses of halogenoalkanes and the regulation of their use, CFCs and their effect in the upper atmosphere and heating under reflux.
Where it is assessed
Components 1 and 2
the Core Ideas, Principles and Concepts, which are examined on both written papers and drawn on again in Component 3.
Check the Eduqas specification ↗The 7 subtopics
Each one has its own page.
- Nucleophilic substitution of primary halogenoalkanesMechanism by which hydroxide ions react with a primary halogenoalkane and leaving group.Open →
- Elimination reactions forming alkenesRecall questions on the reagent and conditions for elimination, the hydroxide ion acting as a base rather than a nucleophile, the equations and the products besides the alkene, why some halogenoalkanes give two alkenes, which class gives the most elimination, and how the solvent decides the outcome.Open →
- Bond polarity, bond enthalpy and the ease of substitutionTrend in carbon-halogen bond enthalpy down the group and why fluoroalkanes are almost completely unreactive towards nucleophiles.Open →
- The silver nitrate test for halogenoalkanesReagents used in the silver nitrate test on a halogenoalkane and chemistry behind the appearance of a precipitate in this test.Open →
- Uses of halogenoalkanes and the regulation of their useThree important classes of use for halogenoalkanes and modern class of refrigerant introduced to replace the chlorine-containing compounds.Open →
- CFCs and their effect in the upper atmosphereFunction of the ozone layer and international agreement under which CFC production was phased out.Open →
- Heating under refluxHeating a reaction mixture under reflux and arrangement of the apparatus used for reflux.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
Describe the three curly arrows in the elimination of hydrogen bromide from 1-bromopropane.
Key term
Explain why the carbon atom bonded to the halogen in a halogenoalkane carries a partial positive charge.
Key term
Place the C—F, C—Cl, C—Br and C—I bonds in order of decreasing polarity.
Key term
State the reagents used in the silver nitrate test on a halogenoalkane.
Key term
Name a halogenoalkane once widely used as a solvent for degreasing and paint stripping.
Key term
What is a CFC?
Key term
Why must the top of the reflux condenser be left open to the air?
Process
Name the mechanism by which hydroxide ions react with a primary halogenoalkane.
Key term
Explain why the C—F bond is the most polar of the four carbon-halogen bonds.
Key term
Why is ethanol added in the silver nitrate test on a halogenoalkane?
Key term
Give two reasons why the use of many halogenoalkanes is now tightly regulated.
Key term
Write the equation for the photodissociation of dichlorodifluoromethane in the stratosphere.
Key term
Why is a water bath or electric heating mantle used rather than a Bunsen flame when refluxing an organic mixture?
Key term
Describe the second curly arrow in the reaction of hydroxide ions with bromoethane.
Key term
Name the class of organic product formed when a halogenoalkane undergoes elimination.
Key term
Place 1-chlorobutane, 1-bromobutane and 1-iodobutane in order of increasing rate of hydrolysis.
Key term
State the temperature at which the silver nitrate test mixture for a halogenoalkane is kept and how that is achieved
Key term
Name a modern class of refrigerant introduced to replace the chlorine-containing compounds.
Key term
Write the equation for the reaction of a chlorine radical with ozone.
Key term
Describe the reflux preparation of butan-1-ol from 1-bromobutane.
Take Halogenoalkanes further
The same content, four other ways.
Questions from this topic
Each one with the model answer underneath.
- 1
Explain why the carbon atom bonded to the halogen in a halogenoalkane carries a partial positive charge.
Model answer
The halogen is more electronegative than carbon, so it draws the bonding pair towards itself and leaves the carbon atom electron deficient.
- 2
Name the mechanism by which hydroxide ions react with a primary halogenoalkane.
Model answer
The mechanism is nucleophilic substitution.
- 3
Why is the hydroxide ion described as a nucleophile?
Model answer
It carries lone pairs of electrons on the oxygen atom and a negative charge, so it donates a pair to an electron-deficient carbon.
- 4
Describe the first curly arrow in the reaction of hydroxide ions with bromoethane.
Model answer
An arrow runs from a lone pair on the oxygen of the hydroxide ion to the δ+ carbon atom, showing the new carbon-oxygen bond being formed.
- 5
Describe the second curly arrow in the reaction of hydroxide ions with bromoethane.
Model answer
An arrow runs from the middle of the C—Br bond to the bromine atom, showing heterolytic fission that releases a bromide ion.
- 6
From which direction does the nucleophile approach the carbon atom in this reaction, and why?
Model answer
It approaches from the side opposite the halogen, because that keeps it as far as possible from the electron-rich leaving group.
What is inside Levo
Six ways to work the same material.
Halogenoalkanes revision questions
- What does Halogenoalkanes cover in Eduqas A-Level Chemistry?
- 7 subtopics: nucleophilic substitution of primary halogenoalkanes, elimination reactions forming alkenes, bond polarity, bond enthalpy and the ease of substitution, the silver nitrate test for halogenoalkanes, uses of halogenoalkanes and the regulation of their use, cfcs and their effect in the upper atmosphere and heating under reflux. Each one has its own page with questions and model answers.
- How is Halogenoalkanes organised?
- By the Eduqas A410QS specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Halogenoalkanes, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.