Summarize the key instructions for conducting practical chemistry exams, focusing on supervisor reports, candidate safety, and procedural integrity.

Here's a summary of the instructions from the Supervisor's Report:

11. Supervisor's Report Forms must be enclosed in each envelope containing scripts.
12. The Chemistry teacher must perform the titrations for Question 1, ensuring figures are recorded to at least one decimal place and carefully verified. This should be done concurrently with the candidates' titrations to prevent unfair penalization due to variations.
13. Any difficulties encountered by candidates should be reported, particularly if an Examiner would not otherwise discover them from the scripts.
14. Candidates must be reminded that chemicals are dangerous if not handled correctly. Before the practical exam, the following safety instructions should be read aloud: handle chemicals carefully, report any unusual sensations to the invigilator, wash the mouth thoroughly with water if chemicals get into it, and wash hands thoroughly after handling chemicals.
15. Appropriate arrangements are expected to be in place to prevent any accident.