1、Review of A-level Chemistry ContentDavid Read June 2007School of ChemistryUniversity of SouthamptonIncludes: AQA, Edexcel, Edexcel Nuffield, OCR and OCR Salters Current specifications onlyComparisons with the new (2008-) specifications will follow.This edition was created on 15/06/07 with correction
2、s2AimThe aim of this review is primarily to show university academic staff what is taught at A-level. It will also form a useful starting point for ascertaining the impact of the new (2008) specifications on the material that will be taught to future A-level students.It should be pointed out that th
3、e review is based on exam board specifications. It should be recognised that although the exam board may not require a particular item to be taught, it is quite possible that it has been covered by teachers. Chemistry teachers do a brilliant job of motivating and enthusing students, and the recent i
4、ncreases in uptake at A-level and in university applications are in no small part attributable to the enthusiasm and hard-work of classroom practitioners.The depth of coverage in different schools will be variable for a number of reasons (I speak from my own experience as an A-level teacher in a com
5、prehensive school with 20+ students doing chemistry), and academic staff should be aware of the following points:a) Unfortunately, teachers performance is judged on exam results, and it is sometimes in their interests to spend time preparing students to do well in exams. Furthermore, many students e
6、xpect a degree of exam coaching in their lessons which puts more pressure on teaching time, and reduces scope for extending teaching beyond the syllabus.b) A majority of A-level chemists will not be doing chemistry degrees, so preparing students for a chemistry degree is not a priority for most chem
7、istry teachers.c) Facilities for practical work (fume cupboards, equipment) are somewhat variable and some students will have very limited practical experience.d) In some cases, non-specialist teachers will be involved in A-level teaching because of a shortage of chemistry teachers. We need to be su
8、re to support these brave people (I wouldnt be able to teach A-level physics or biology!) by sharing good practice.e) In many cases, teachers are faced with very mixed ability (and sometimes quite large) classes, which inevitably means that more difficult topics are harder to deliver.As is seen at u
9、niversity level, students do have short memories sometimes, and they may well need to be reminded about what they were taught at A-level! This is perhaps an unfortunate consequence of the modularisation of the A-level course which allows students to compartmentalise their knowledge, which can lead t
10、o its disposal after the exam. It should not therefore be expected that first year undergrads will have a thorough working knowledge of the material that they were taught as shown in this document! 3Using this documentI have put together this review of A-level chemistry content by referring primaril
11、y to the exam board specifications themselves. To make it accessible for academics, I have tried to break it into Inorganic, Organic and Physical, although this distinction is not necessarily made now in teaching at A-level, especially since the modular courses were introduced in the 1990s. Interest
12、ingly, our own students at Southampton University tell us that they like their teaching to be delivered in terms of I, O and P as this helps them to identify areas of weakness.In each section, I have reviewed the content of the 5 main (English) specifications (see Appendix B for more detail). Topics
13、 are listed on the left, and coverage in a particular specification is indicated by a /, while the absence of that topic is denoted by X. In some cases AS or A2 are used to indicate that the topic in question is covered elsewhere. In the case of Edexcel Nuffield and (most notably) OCR, OPT will be s
14、een when material is covered in an optional module. Coverage of the optional modules included in these specifications is limited to that which overlaps with the mainstream content of other specifications (see Appendix A for more detail).Entries in bold beginning Students should be able to are there
15、to help communicate what the students should be capable of. I remind the reader that should is a very vague term The demand of the topic entries is variable, and I have made no attempt to suggest grade levels for them.I apologise at this point for any incorrect information, and I welcome reports of
16、errors for correction (d.readsoton.ac.uk). As stated elsewhere, this document is meant to be an overview, although it has admittedly become somewhat larger than originally envisaged! For truly comprehensive records of what each board requires, please refer to the specifications.From my own perspecti
17、ve, it has been a useful process as I have been able to identify the gaps in different specifications, which will help me to develop support for undergraduates who come in with different A-level backgrounds. Some interesting headlines are that the OCR specification is the only one that makes no ment
18、ion of entropy, a significant omission, some might suggest. SN1 and SN2 reactions only crop up in the two Edexcel specifications (the others cover nucleophilic substitution in a generic sense), while AQA is the only board to cover the ideal gas equation and Gibbs free energy. These are just a few of
19、 the differences that can be found between the different specifications. DR 06/074ContentsPage AS chemistry6 General chemistry6 atomic structure7 moles and equations8 covalent bonding and shapes of molecules9 ionic, metallic and giant covalent structures10 intermediate bonding and intermolecular for
20、ces11 Inorganic chemistry11 the periodic table and periodicity12 redox processes13 s-block elements14 halogens and halides15 Organic chemistry15 nomenclature and isomerism 17 hydrocarbons19 halogenoalkanes20 alcohols and their reactions21 Physical chemistry21 energetics22 kinetics23 equilibria24 A2
21、chemistry24 General chemistry24 spectroscopy26 Inorganic chemistry26 transition metals, complex ions and metal-aqua ions28 behaviour of different transition metals29 the elements of period 330 Organic chemistry30 isomerism and further mechanism31 aldehydes, ketones, carboxylic acids, esters and acyl
22、 chlorides5Page A2-Level chemistry continuedOrganic chemistry continued33 aromatic compounds (inc phenols)34 amines, amides, azo dyes and amino acids36 polymers37 Physical chemistry37 energy and thermodynamics38 kinetic theory39 equilibria40 acids endothermic reactions take heat energy in.Students s
23、hould be able to draw enthalpy profile diagrams with labels to illustrate exo- and endothermic reactions, showing H and Ea. (understanding of the term enthalpy is often woolly)/ / / / /Exothermic reactions are not necessarily spontaneous and some endothermic reactions are. (no treatment of entropy o
24、r Gibbs at AS level EXCEPT Salters see later on this page)Students should be able to give a qualitative description of the difference between thermodynamic and kinetic stability.X / X X XEnthalpy changes can be worked out using q=mcT.Students should be able to describe/plan experimental techniques t
25、o work out enthalpy changes (this is covered more specifically by the Edexcel + Nuffield specifications)./ / / / /Enthalpy changes can be worked out indirectly by applying Hesss Law.Students should be able to draw enthalpy cycles to illustrate how they use enthalpy values to calculate enthalpy chang
26、es./ / / / /Breaking bonds is an endothermic process while making bonds is exothermic.Students may be aware of the link between bond length and bond strength. / / / / /Entropy is a measure of the disorder of a system.Students should be able to give a qualitative description of the trend in entropy o
27、n going from solid liquid gas. (More coverage in A2 not Edexcel or OCR)X X X X /22AS level physical chemistry - kineticsTopic AQA Edexcel EdexcelNuffield OCR OCRSaltersParticles must collide to react.Students should be able to describe and explain the effect on rate of reaction of changing concentra
28、tion, pressure and surface area. They should be able to explain what is meant by activation energy using an enthalpy profile diagram free radical, photochemical reaction; chain reaction; initiation; propagation termination; nucleophile and electrophile; addition, substitution, elimination and hydrolysis.Other mechanisms are covered elsewhere in this section on A2 level organic chemistry.
