A chemistry exam question asks students to identify substances, concentrations, and procedures for titration and reaction analysis.

Here is a summary of the instructions:

3. Each candidate should be supplied with the following, where "n" is the candidate's serial number:
   • a) 150 cm$^3$ of H$_2$SO$_4$ solution (labelled 'An') in a corked flask or bottle. This solution must contain 5.60 cm$^3$ of concentrated H$_2$SO$_4$ (R.D. 1.84 and purity 98%) per dm$^3$ of solution.
   • b) 150 cm$^3$ of NaOH solution (labelled 'Bn') in a corked flask or bottle. This solution must contain 4.0 g of NaOH per dm$^3$ of solution.
   • c) One spatulal of 1:1 uniform mixture of lead (II) carbonate and starch in a specimen bottle (labelled 'Cn'). This mixture must be the same for all candidates.
4. More materials may be issued if required.
5. The actual concentrations of A and B must be stated on the Supervisor's Report Form. Candidates will assume these concentrations are exactly as stated in the question paper.
6. Schools are not allowed to amend information or substitute any substance/solution from those specified in these instructions.
7. Laboratory places should be numbered serially, and candidates allotted places strictly in the order of their index numbers. The number of every specimen supplied must correspond to each candidate's serial number.
8. If a candidate is absent, their serial number should not be allotted to another candidate.
9. If candidates are divided into sets, the serial numbers should be continued through the sets to ensure no serial number is repeated.
10. At the beginning of the examination, ensure candidates record their serial numbers and index numbers on the front pages of their answer booklets, as they will be marked according to their serial numbers.