When the Revised Higher was introduced in 2011, two exemplars for the Researching Chemistry Unit were produced: antioxidants and alcohols.
At the same time, however, a biodiesel exemplar was also submitted. Somewhere it went astray, not helped by the fact that this was around the time that LTS became ES.
We reworked this in 2014 and submitted it - just as the assignemtns changed - it is still a valid investigation though.