Please draw all graphs on graph paper or use a computer program such as Excel or OfficeHD both result tables.
answer these questions :
1. How do you determine the wavelength at which to set the spectrophotometer?
2. What should you do if your unknown solution shows an absorbance reading of 2.3?
ULTRAVIOLET/VISIBLE (UV/VIS) SPECTROSCOPY
The chemicals listed below will be used in this experiment. The likely hazards associated with each of the chemicals are noted and recommended procedures for handling are given. You must read this page and the experimental description carefully before starting the experiment and before coming into the laboratory. Note any potential hazards and adopt precautions as your safe lab practice. When you are satisfied that you understand any possible difficulties that might arise and the recommended procedures for dealing with them, sign the declaration and have it initialled by a demonstrator. This must be done prior commencing lab work. At the beginning of the lab session demonstrators will quiz you about the safety information and experimental procedure in order to identify your ability to work safely and efficiently. If you fail to prove the ability for safe and efficient work you will not be allowed to start lab practical. Please note that it is you own responsibility to complete the lab practical during time that is allocated to you. Be sure to request information or help if you are in doubt on any point.
Chemical Hazard Precautions
Phosphate solution Irritant Do not ingest, avoid skin/eye
contact, wear gloves
Acid molybdate solution Corrosive Do not ingest, avoid skin/eye
contact, wear gloves.
Ascorbic acid solution Irritant Do not ingest, avoid skin/eye
contact, wear gloves.
Carefully observe the instructions regarding clean-up of the apparatus. Take great care when handling materials to avoid spillage, splashing etc. Do not ingest and do not breathe chemical vapours. In case of accident or if you feel unwell, report to a member of staff and seek medical advice immediately.
Declaration – I have read and understood the contents of the safety information sheet and the script for the experiment