Chemistry (OCR B, Single Science, Foundation) Chemicals of the Natural Environment (OCR B, Single Science, Foundation) C3.4 Chemicals of the natural environment – Part 2 – Crude oil (Chemistry only) (OCR B) Lesson Progress C3.4 Chemicals of the natural environment – Part 2 – Crude oil (Chemistry only) (OCR B) Previous Topic Back to Lesson Previous Topic Back to Lesson