Determining Price of Ethanol: Example Problem
Not what you're looking for?
I am having trouble determining what I should do in this problem. I believe I start by figuring out the combustion reactions for ethanol and octane.
For ethanol I have: C2H5OH(l)+ 3O2(g) = 2CO2(g) + 3H20(l)
For octane I have: C8H18(g) + 25/2 O2(g) = 8CO2(g) + 9H20
I am lost on what to do next or what I should do with these formulas. I do not understand what to do with the Hf, KJ/mole for octane and ethanol.
The problem is:
Two fuels available for automobile uses are ethanol (C2H5OH) and gasoline (assume it to be octane, C8H18). If gasoline is selling for $2.70/gallon, what would the price of ethanol have to be in order to provide the same amount of heat/dollar? The heat evolved for each fuel can be found by calculating the heat released in the combustion reaction for each fuel. 1 gal = 3.785 L
Octane -249.9 Hf, KJ/mole
Ethanol -277.0 Hf, KJ/mole
Octane 0.7025 density, g/ml
Ethanol 0.7894 density, g/ml
Purchase this Solution
Solution Summary
The solution provides steps necessary to determine the price of ethanol.
Purchase this Solution
Free BrainMass Quizzes
Functional groups in Organic Chemistry
You will be tested on the names of functional groups in Organic Chemistry. It is very important to know the functional groups to understand Organic reactions.
Thermochemistry
The quiz helps in revising basic concepts about thermochemistry.
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.
Match Elements with their Symbols
Elements are provided: choose the matching one- or two-letter symbol for each element.