Two or three drops of fuel! The stoichiometric AFR for isopropanol is 10.4:1 according to the sources I found. For 1g of fuel you need 10.4g of air which at SS

Two or three drops of fuel! The stoichiometric AFR for isopropanol is 10.4:1 according to the sources I found. For 1g of fuel you need 10.4g of air which at SSL[1] corresponds to around 8.5L. One drop of fuel does consume several liters of air to burn. The volume difference is really that huge --- and the higher the AFR, the bigger the difference; gasoline engines are around 14.7:1, and diesels go much higher when idling or under light load. Relatedly, fuel economy expressed as an area: http://theskepticalzone.com/wp/weirdly-fuel-efficiency-can-be-expressed-as-an-area/comment-page-1/ http://theskepticalzone.com/wp/weirdly-fuel-efficiency-can-b... [1] https://en.wikipedia.org/wiki/Standard_sea-level_conditions https://en.wikipedia.org/wiki/Standard_sea-level_conditions