1. A2 Chemistry Support Events
Wednesday 6th December 2017: Springvale, Belfast
Thursday 7th December 2017: Glenavon Hotel, Cookstown
Tuesday 12th December 2017: Armagh City Hotel

2. Welcome and Introductions…
Subject Officer: Elaine Lennox
Tel: Ext. 2320
Specification Support Officer: Barbara Laffitte-Fitou
Tel: Ext. 2292
Chair of Examiners: Billy McAlpine

3. Programme General specification information A2 3 Practical Assessment
Training on drawing chemistry diagrams and molecules
Mathematics – Examiner expectations
Q & A Session

4. Assessment Weightings

5. Teacher Support Support Direct access to Subject Officer
Dedicated microsite with News and Events
Specification
Specimen Assessment materials
Past papers and Mark Schemes
Editable Scheme of Work
Student Guide
Acceptable Colour Changes document
Clarification of Terms document
Grade Boundaries and Outcomes
AS and A2 Factfiles for every topic (Remainder coming soon)
Answers to Factfile Questions
AS and A2 Practical Guidance Document
Videos of Interviews with University and Industry representatives
Videos of Experiments
Centre Support visits
Support Days
Textbooks and Revision Guides (not CCEA endorsed)
Teacher Support

6. Teacher Support Support coming soon…
Exemplifying Examination Performance materials
AS Support Event in 2018 focusing on EEP material and Assessment Objective training
AS and A2 Practical Manual with Technician Notes
Document to support teaching the mathematics on the specification
Teacher Support

7. A2 3 Practical Support

8. Grade Boundaries AS 3 (New) – 2017
AS 3 (Practical Booklets A and B Combined)
Raw
(80) UM
(48) A 60 39 B 52 34 C 45 29 D 38 24 E 31 20

9. JCQ Centre Inspection Service
AS 3 and A2 3 practical examinations are on the programme for the JCQ Centre Inspection Service.
The inspectors are provided with a list of ‘Inspection Objectives’ specifically for the practical aspects which are conducted in science laboratories.
If they are visiting before the exam has been scheduled to take place, they need to see the Examination’s Officer to ensure the Question papers are still sealed before they go to the examination room.

10. A2 3 Practical Work
carry out experiments to determine the rate of a reaction using a variety of methods to determine the concentration of reactants and/or products
make buffer solutions from calculated quantities of salts and acids and determine their pH values using universal indicator (UI) paper and a pH meter
determine the shape of a titration curve by measuring the pH using specialised pH paper or a pH meter for the titration of an acid with a base
determine the pH of a variety of salts using pH paper or a pH meter to illustrate the relative strength of acid and base

11. prepare, recrystallise and determine the melting point of 2,4-dinitrophenylhydrazone
use Fehling’s solution and Tollens’ reagent to distinguish between aldehydes and ketones
prepare a carboxylic acid from an alcohol
carry out test tube reactions of a carboxylic acid with sodium carbonate, sodium hydroxide and aqueous ammonia and measure the pH changes
prepare a liquid ester from a carboxylic acid and an alcohol

12. titrate iodine with sodium thiosulfate using starch and hence estimate oxidising agents by their reaction with excess acidified potassium iodide
titrate acidified potassium manganate(VII) with reducing agents
determine the purity of a Group II metal oxide or carbonate by back titration
carry out paper and thin-layer chromatography and measure the Rf values of the components and interpret the chromatograms
use ethylene diamine, phenylamine and aqueous ammonia to demonstrate ligand replacement based on lone pair availability

13. demonstrate the relative strengths of ligands using hydrated copper(II) ions and hydrochloric acid
carry out qualitative detection tests for the formation of transition metal hydroxides with sodium hydroxide and aqueous ammonia
carry out the reduction of acidified ammonium metavanadate with zinc and observe the sequence of colours
determine the electrode potentials of a series of cells and predict their values using standard electrode potentials

14. determine the amount of a carbonate, for example calcium carbonate or magnesium carbonate, in an indigestion tablet
prepare aspirin using salicylic acid and ethanoic anhydride
use chromatography to compare the purity of laboratory made aspirin with commercial tablets

15. Format of Assessment
Practical Booklet A consists of a variety of practical tasks (30 marks). Students take the assessment in the laboratory. Duration 1 hour 15 minutes.
Practical Booklet B consists of a variety of questions testing knowledge of practical techniques, observations and calculations (60 marks). Students take the examination in an examination hall. Duration 1 hour 15 minutes.
Both timetabled

16. General Points Apparatus & Materials list to centres in February
Teacher’s copy of paper available to HOD
3 working days before timetabled starting time
Practical Booklet A only
Confidentiality – keep doors locked, papers locked away etc.
More than one sitting – pupils in isolation ½ hour before the end of the first sitting
Follow JCQ Instructions – remove mobile phones etc.
AS and A2 Practical Booklet A Invigilation:
Teacher who prepared the class cannot be the sole invigilator
Needs to be a chemistry teacher present

17. Booklet A
The objective of Booklet A to assess scientific skills and so may include the use of chemicals/materials and/or contexts unfamiliar to students in addition to those listed in the specification.
Assessment may include the following: observation, recording, analysis/processing of results, risk assessment, drawing scientific diagrams, variables and scientific methodology.

18. Specimen Assessment Materials

21. Booklet B
The objective of Booklet B to assess practical theory, deductions and calculations in familiar and unfamiliar contexts.
Assessment may include the following: analysis/processing of secondary data, risk assessment, drawing scientific diagrams, variables and scientific methodology and uncertainty in measurement.

22. Specimen Assessment Materials

23. In order to facilitate efficient use of resources with in the lab, eg fume cupboards, candidates do not need to complete the questions set in Booklet A in the order presented in the paper.
Small changes in solution concentrations or apparatus are permissible in order to observe the anticipated observations during trials. CCEA do not have to give permission for this.

24. Practical Support The practical support document
gives guidance regarding practical
experiments indicated in the
specification.
These may be adapted as
required to suit individual school
requirements.

25. Frankly Chemistry… Preparation of methyl 3-nitrobenzoate.

26. Training on drawing chemistry diagrams and molecules

27. Diagrams – Common Errors

36. Mechanisms & Curly Arrows

42. Examiner expectations Mathematical requirements of the specification
Mathematics
Examiner expectations
Mathematical requirements of the specification
are listed on pages 49-54

43. General
The requirement is 20% maths content across the series – for chemistry it will probably be higher than this, as equations count as mathematics.
Questions will be phrased as much as possible to minimise mathematical error for example by stating the number of significant figures required or the number of decimal places. Eventually it is hoped to phase out such statements in questions because the new mathematical requirements should be inherent in the GCE chemistry examinations.

44. Significant Figures
You need a decimal point to determine a significant figure. A useful way of visualising significant numbers is to use scientific notation. Hence is 1.23 x and there are three significant figures or 2000 is x 103 and there are 4 significant figures. We have already altered our procedure with regard to the 250 cm3 volumetric flask which we are now calling cm3.
Students must report calculations to an appropriate number of significant figures given raw data quoted to varying numbers of significant figures and must understand that calculated results can only be reported to the limits of the least accurate measurement. For example, in the calculation × 2.0 = ≈ 2.5, the first factor has four significant figures and the second has two significant figures. The factor with the least number of significant figures is the second one with only two, so the final calculated result also has a total of two significant figures. For quantities created from measured quantities by addition and subtraction, the last significant decimal place in the calculated result should be the same as the leftmost or largest decimal place of the last significant figure. For example,
= ≈ 101.2

45. RAMs & % Uncertainty
The RAMs are quoted to a variety of significant figures e.g. hydrogen = 1 ( 1 sig fig) oxygen =16 (2 sig fig) silver = 108 ( 3 sig fig). RAMs are treated in the same way as π (3.142) i.e they are treated as exact numbers. Exact mathematical quantities like π have no effect on the number of significant figures. The constant π is considered to have an infinite number of significant figures. It is an exact number stated by law or by definition.
At the moment there is no intention to do “physics uncertainty” on the whole aspect of a titration. The phrase % uncertainty is not used in the specification but it should be capable of being deduced. CCEA will also use the word error.

46. Apparatus Accuracy
It would be wrong to say that volumetric flasks have a definite uncertainty. It depends on the quality of the flask, some are more accurately constructed than others i.e. different classes. A 250 cm3 volumetric flask with an uncertainty of ± 0.2 cm3 has a % uncertainty of 0.2/250 x 100 = 0.08 %.
Class A pipettes have an accuracy of 0.1% and Class B pipettes have an accuracy of 0.2%. This means, with a 25 cm3 pipette, class A is ± cm3 and class B is ± cm3. This has an implication for titrations; some authors quote a pipette with ±0.06 cm3.

47. The accuracy of a burette varies with its class and with its volume
The accuracy of a burette varies with its class and with its volume. Pipettes and volumetric flasks have a set volume but burettes do not.
Accuracy varies from 0.10% to 0.40% although it depends on the volume delivered.
Capacity /cm3
Class A/cm3
Class B/cm3 10
0.02
0.04 25
0.03
0.06 50
0.05
0.10
100
0.20

48. Titrations
Only concordant results should be used in calculating the mean titre. CCEA has tended to adopt +/-0.2 as being a concordant result in a titration.
The burette reads to an accuracy of 0.1 cm3 but when titre values are taken and then averaged a third decimal place may be created. For example, the average of and is but the burette does not read to a third decimal place. The maths is correct but the chemistry is not. The average could be recorded as 25.2, 25.20, or or All of these values would be marked as chemically correct despite the fact that the burette does not read to a third decimal place and it is impossible to read to They are not all mathematically correct as the instruction is not to round off until the end of the calculation or to leave one significant figure more than required. If the calculation has finished at this stage it is acceptable if the final titration result (average/mean) is being presented as the unrounded figure of

49. Tangents & Accuracy/Precision
Students must be able to draw and use the slope of a tangent to a curve as a measure of rate of change. The reaction at time zero approximates to a straight line and there is no need to draw a tangent to a curve. Any examination questions will present a reasonable amount of a straight line in order to draw an appropriate “tangent”.
In chemistry, accuracy refers to how close a measurement is to its standard or known value. Precision refers to how close two or more measurements are to each other, regardless of whether those measurements are accurate or not.

50. Rounding
Incorrect rounding is penalised. In general do not round off until the end of the calculation (leave all calculator values) or to leave one significant figure more than required at each step. Fractions are acceptable until the final answer.

51. ?
Q&A