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Welcome to ChemRevise (or welcome back)

It’s the start of a new academic year so welcome back.

I get lots of questions about whether ChemRevise notes say everything that is needed to do well at A-level. I ought to point out when I originally wrote these notes they were aimed as brief revision notes for my own students. My expectation was that they had done two years of hard  work, answering many questions and fully understood all that we have covered in class. They cannot be a replacement for this hard work.  There is no quick route to success at A-level. These notes can make revision more manageable and they have been used successfully by many thousands of students.

I have more recently made detailed notes in the section called text book that could help deepen your understanding. Some of these chapters have questions.

I hope you have a good year.

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Updates to A-level Textbook

I had a bit of a spurt of effort on my e-text book project over Easter and it is now all in the same format. It is very much an ongoing project though. At the moment it as an amalgamation of all the written material I have consolidated from various sources of mine. It is not therefore syllabus specific. Some material may be the same as what is on the revision guides. Some has more extensive explanations or I have tried to look at things from a different angle. Some material is also extension to A-level. Over time I will add to the explanations to turn the revision guide bits into something more detailed. I will also add to the questions that appear in some chapters.

International A-level Chemistry for CIE and Edexcel

There are two completely new sets of guides.  One for CIE (Cambridge International Assessments) and one for international Edexcel. They have both been written for the new syllabi. So if you are taking exams in 2018 they may not be an exact match. Changes are relatively minor though. They are very different syllabi so make sure you revise the right one.

Find here

Practical Guides 2018

I have said I was not going to produce a practical revision guide. My own pupils have persuaded me of the case to do something though.

I have taken existing relevant notes and arranged them in basic order of syllabus/required practicals. In addition I have added more detailed descriptions of the methods for the various practicals.

I have also added practicals that are not required but I think are important to know.

I have not necessarily used the exact ‘exam board’ methods.

There is an AQA   Practical Guide -aqa

An OCR Practical Guide OCR version.

An edexcel Practical Guide Edexcel version

Updates to A-level calculation guides

I have quite significantly enlarged the guides for the calculation topics for the AQA, OCR and Edexcel. It is mostly more worked examples of different sorts of possible calculations.

These are the updated files

AQA 1.2 revision guide calculations

OCR 2.1.3 amount of substance

OCR 2.1.4 acids

Edexcel 5. formulae equations and amount

If you are looking for questions to do you will find them on the  text book page 

 

GCSE revision guides for AQA

I have put together a set of revision guides for the 2018 new AQA GCSE chemistry. They are in syllabus order, which is not the order I teach the course but when it comes to final revision will be the most useful order. It is very much a first draft  for these and no doubt they will change over time.  Find the page here

AQA Paper 3

People have kept asking for a guide on the practicals. As I have explained before I am not producing one. It is worth remembering paper 3 is only partially practical based. There will be multiple choice questions and short answer questions on all parts of the syllabus. There are no short cuts. You need to know everything practical or non practical. It is not going to be an easy paper.

You will need to know the 12 required practicals but you will also get questions on other practicals which may be unfamiliar.

Practical questions could be about:

  • write the method for a common practical
  • draw diagrams of common apparatus
  • create a method for an unusual experiment
  • suggest improvements to a given method
  • state why a step in a method is done
  • draw graphs, take gradients and make conclusions from given results
  • see if results confirm a given hypothesis
  • give expected observations for a reaction
  • write chemical equations that match observations given
  • describing  causes of common errors
  • explain how errors could be minimised
  • explain what effect errors might have on the result

The 12 required practicals for AQA are given below with the relevant revision guides where I have mentioned them.  For some I have included brief methods where I think they are needed but not all. You should refer to your practical work for the full methods or the AQA practical handbook.

1 Make up a volumetric solution and carry out a simple acid–base titration – s1.2 revision guide calculations and  see 1.25 titrations for lots of questions on errors and method

2 Measurement of an enthalpy change see 1.4 revision guide energetics

Consider – neutralisation reactions, solution plus solid and combustion reactions

3 Investigation of how the rate of a reaction changes with temperature see 1.5 Kinetics

Usually sodium thiosulphate and acid –the result from this experiment can be used to work out activation energy see 1.9 Rate Equations

4 Carry out simple test-tube reactions to identify:

 

5 Distillation of a product from a reaction   see3.5 revision guide alcoholss and 3.14 Synthetic routes

 

 6 Tests for alcohol, aldehyde, alkene and carboxylic acid  see 3.6 Analysis and 3.14 revision guide organic synthesis

7 Measuring the rate of reaction:  see 1.9 Rate Equations or  4. Reaction Kinetics

  •  by an initial rate method – generally ‘clock reactions’ or timing how long it takes for a cross  to disappear
  • by a continuous monitoring method- generally following with a gas syringe, but could be titration of samples or colorimeter

8 Measuring the EMF of an electrochemical cell   see 1.11 Redox Equilibria

9 Investigate how pH changes when a weak acid reacts with a strong base and when a strong acid reacts with a weak base   see 1.12 revision guide acid base equilibria

10 Preparation of: 

11 Carry out simple test-tube reactions to identify transition metal ions in aqueous solution see 2.5 Transition Metals  and 2.6. Reactions of Inorganic Compounds in Aqueous Solution

12 Separation of species by thin-layer chromatography see  3.16 Chromatography and 3.13 revision guide amino acids proteins and DNA

Other important experiments commonly asked about in the past that could still well come up:

Simple measuring mass and gas volume experiments such a heating a hydrated salt or measuring the Mr of a volatile liquid see 1.2 revision guide calculations

Colorimeters see 2.5 Transition Metals

Redox titrations and EDTA titrations see 2.5 Transition Metals

Autocatalysis reaction see 2.5 Transition Metals

Measuring an equilibrium constant for an esterification reaction 1.6 revision guide equilibria

Comparing rates of hydrolysis of halogenoalkanes see 3.3 Halogenoalkanes

Any test tube reaction from inorganic or organic part of syllabus

Don’t forget

Calculating uncertainties and safety see 1.2 Calculations

 

 

February updates 2017

A few updates (mostly to AQA notes). Some students have been asking for a practical revision guide. I will not be producing one at the moment. I took the decision to integrate the practical notes into the relevant chapters with the linked theory, and I think this is the best way to approach the practical material. The AQA paper 3 will be a combined practical and synoptic theory paper.

I have done some updates to practical material though, notably in 1.6 revision guide equilibria where I have included extensive notes on the practical measuring kc. This is not actually a required practical but it has been a favourite in the past on AQA practical papers. I have also included notes on solving equilibrium constant equations algebraically  which I think are going to appear on the new exams (although not with quadratic equations).

I have changed terminology in 1.2 revision guide calculations to use uncertainty instead of error.

The other chapters I have changed have been labelled with (updated February 2017)

I have also produced a aqa-mechanisms-a-level-summary for the new syllabus