1. Great care should be taken to ensure that the information given in the items 2 and 3 below does not reach the candidate either directly or indirectly before the examination.
2. In addition to the fittings and reagents normally found in a chemistry laboratory, the following apparatus and materials will be required by each candidate:
(a) One burette of 50 cm3 capacity;
(b) One pipette, either 20 cm3 or 25 cm3. (All candidates at one centre must use pipettes of the same volume. These should be clean and free from grease)
(c) The usual apparatus for titration;
(d) The usual apparatus and reagents for qualitative work including the following with all reagents appropriately labelled;
(i) Dilute sodium hydroxide solution;
(ii) Dilute hydrochloric acid;
(iii) Dilute trioxonitrate
(V) acid;
(iv) Silver trioxonitrate
(V) solution;
(v) Acidified potassium dichromate solution;
(vi) Aqueous ammonia;
(vii) Lime water;
(viii) Red and blue litmus paper
(ix) Dilute tetraoxosulphate (VI) acid;
(x) Fehlings solution A & B.
(e) Spatula;
(f) Filtration apparatus;
(g) One beaker
(h) One boiling tube;
(i) Four test tubes;
(j) Methyl orange as indicator;
(k) Glass rod;
(l) Wash bottle containing distilled/deionized water;
(m) Burning splint;
(n) Watch glass;
(o) Bunsen burner/source of heat;
(p) Droppers;
(q) Mathematical table/calculator.
3. Each candidate should be supplied with the following, where ‘n’ is the candidiate’s serial number.
(a) 150 cm3 of a solution of HCl in a corked flask or bottle labelled ‘An’. These should all be the same containing 8.5 cm3 of concentrated HCl per dm3 of solution.
(b) 150 cm3 of Na2CO3.10 H2O in a corked flask or bottle labelled ‘Bn’. These should all be the same containing 5.0 g of the hydrated salt per dm3 of solution.
(c) One spatulaful of glucose in a specimen bottle labelled ‘Cn’. This must be the same for all candidates.
(d) One spatulaful of zinc oxide powder in a specimen bottle labelled ‘Dn’. This must be same for all candidate.
4.In all cases, more materials may be issued if required.
5.The actual concentrations of A and B must be stated on the Supervisor’s Report Form. The candidates will assume that the concentrations are exactly as stated in the question paper.
6.It should be noted that schools are not allowed to amend the information provided on the question paper or substitute any substance/solution for those specified in these instructions.
ARRANGEMENT AND SERIAL NUMBERS OF CANDIDATES
7.The laboratory places should be numbered serially and the candidates should be allotted these places strictly in the order of their index numbers. The number of every specimen supplied to each candidate should be the same as his or her serial number.
8.If a candidate is absent, his or her serial number should not be allotted to another candidate.
9.If the candidates are divided into a number of sets, the serial numbers should be continued through the sets, so that no serial number is repeated.
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