Home of real teaching & learning
  • Full support for teachers
  • Focus on critical thinking
  • Engaging classroom activities
  • Integrated student eBook
  • Assessed tasks / qBank
  • Practice exam questions

The InThinking Guarantee: Our sites are written by expert practitioners and not by AI

See our AI policy

Disclaimer: InThinking subject sites are neither endorsed by nor connected with the International Baccalaureate Organisation.

Don't miss out, find out!

Fossil fuels answers

1. (a) RON (Research octane number) refers to the auto-ignition tendency for a fuel. The lower the octane number the more likely the fuel is to auto-ignite under compression. Aromatic compounds such as methylbenzene have a higher octane rating than 100 as they are less likely to auto-ignite under compression than 2,2,4-trimethylpentane, i.e. they are less likely to cause ‘knocking’. (b) Octane number = (87/100 x 100)...

Help