(a)
Interpretation: The enthalpy of combustion of ethanol and isooctane, the fuel which release more
Concept introduction:
Enthalpy of combustion: At standard conditions when one mole of substance is burnt completely in presence of oxygen, the enthalpy change involved is called enthalpy of combustion.
(a)
Answer to Problem 47GQ
Isooctane release more energy than ethanol.
Explanation of Solution
Given the combustion of ethanol and isooctane:
Enthalpy of combustion can be calculated by the equation:
Enthalpy of combustion can be calculated by the equation:
Isooctane releases more energy per kilogram.
(b)
Interpretation: compare the enthalpy of combustion of ethanol and isooctane and the fuel which release more
Concept introduction:
Enthalpy of combustion: At standard conditions when one mole of substance is burnt completely in presence of oxygen, the enthalpy change involved is called enthalpy of combustion.
(b)
Answer to Problem 47GQ
Ethanol produces less
Explanation of Solution
One mole of ethanol produces two moles of
The number of moles
One mole of isooctane produces eight moles of
The number of moles
Isooctane release more amount of
(c)
Interpretation: The better fuel in terms of energy production and greenhouse gases should be determined.
Concept introduction:
Enthalpy of combustion: At standard conditions when one mole of substance is burnt completely in presence of oxygen, the enthalpy change involved is called enthalpy of combustion.
(c)
Answer to Problem 47GQ
Isooctane releases more energy, but it releases more
Explanation of Solution
In-order to say whether ethanol or isooctane is a better fuel, we have to compare its energy release.
Comparing ethanol and isooctane, isooctane releases more energy.
But the problem is that when we compare the
On the basis of energy release isooctane can be considered as a better fuel, but when the release of
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Chapter 20 Solutions
Chemistry & Chemical Reactivity
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