Concept explainers
(a)
Interpretation: The balanced equation for the burning of methyl
Concept introduction:
- Balanced chemical equation of a reaction is written according to law of conservation of mass.
- Stoichiometry of a
chemical reaction is the relation between reactants and products of the reaction and it is represented by the coefficients used for the reactants and products involved in the chemical equation.
(a)
Answer to Problem 31PS
The balanced equation for the given reaction is,
Explanation of Solution
When methyl
The balanced equation for the combustion of methyl myristate is given as:
(b)
Interpretation: Enthalpy change for the oxidation of methyl myristate should be determined using the given data.
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 31PS
Enthalpy change is calculated to be
Explanation of Solution
Given:
Change in enthalpy can be calculated by the equation:
(c)
Interpretation: The fuel which provides more energy (Hexadecane or methyl
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 31PS
Hexadecane provide more energy than methyl
Explanation of Solution
For methyl myristate:
Change in enthalpy can be calculated by the equation:
For hexadecane:
Change in enthalpy can be calculated by the equation:
Hexadecane provide more energy than methyl myristate.
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Chapter 20 Solutions
CHEMISTY+CHEMICAL REACTIVITY
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