Fuel Efficiency : Octane versus Ethanol
Not what you're looking for?
If we use octane (C8 H18 ) as the representative of what is contained in gasoline, and compare it to ethanol (C2H5OH), currently a promising substitute for gasoline, what will be the energy difference on a per gram basis for the two? For the reaction of octane with oxygen to produce carbon dioxide and gaseous water, 48.1 kJ of heat are evolved per gram of octane burned. For ethanol, 26.8 kJ of heat are evolved per gram of ethanol burned.
The density of octane is 0.7025 g/cm and the density of ethanol is 0.7893 g/cm . If burning octane in an automobile is 20% efficient (i.e., 20% of the energy produced is used to move the car) and burning ethanol is 25% efficient, which fuel will have the larger tank, and by how much, to have the same mileage capability?
Purchase this Solution
Solution Summary
This solution uses efficiencies of burning octane and burning ethanol to compare the size of a fuel tank needed to provide the same amount of energy.
Solution Preview
Please see the attached file for the complete solution.
Thanks for using BrainMass.
If we use octane (C8 H18 ) as the representative of what is contained in gasoline, and compare it to ethanol (C2H5OH), currently a promising substitute for gasoline, what will be the energy difference on a per gram basis for the two. For the reaction of ...
Purchase this Solution
Free BrainMass Quizzes
Match Elements with their Symbols
Elements are provided: choose the matching one- or two-letter symbol for each element.
Organic Chemistry Naming: Alkanes
This is a quiz which is designed to assist students with learning the nomenclature used to identify organic compounds. This quiz focuses on the organic compounds called Alkanes.
General Chemistry - Classification of Matter
This test will assess your knowledge on the classification of matter which includes elements, compounds and mixtures.
Thermochemistry
The quiz helps in revising basic concepts about thermochemistry.