| Date | May 2017 | Marks available | 1 | Reference code | 17M.3.sl.TZ2.19 |
| Level | SL | Paper | 3 | Time zone | TZ2 |
| Command term | Suggest | Question number | 19 | Adapted from | N/A |
Question
The production of many pharmaceutical drugs involves the use of solvents.
Suggest one problem associated with chlorinated organic solvents as chemical waste.
Suggest how the principles of green chemistry can be used to solve the environmental problems caused by organic solvents.
Markscheme
Any of:
«most are» toxic «to living organisms»
OR
incomplete combustion/incineration can produce toxic products/dioxins/phosgene
OR
carcinogenic
«some can be» greenhouse gases
ozone-depleting
can contribute to formation of «photochemical» smog
accumulate in groundwater
OR
have limited biodegradability
cost/hazards of disposal
Do not accept “harmful to the environment”.
Do not accept just “pollutes water”.
[1 mark]
use organic solvent-free synthetic methods
OR
use water as a solvent
OR
based on atom economy
OR
recover/reuse solvents
[1 mark]
