Concept explainers
(a)
Interpretation:
Enthalpy change for the combustion of 1 mol of
Concept Introduction:
The
The equation that describes the bond dissociation for
Bond energies are always endothermic and have a positive sign. It takes energy to break a bond.
The enthalpy of reaction can be determined by the sum of the bond dissociation energies of all the reactants minus the sum of the bond dissociation energies of all products present in
The equation to calculate enthalpy of reaction is as follows:
Negative sign in the equation depicts that bonds will form in the products. It is an exothermic process, so the energy charge is the negative of bond energy.
(b)
Interpretation:
The approximate enthalpy change for the reaction of formaldehyde and molecular hydrogen to form gaseous methanol has to be determined.
Concept Introduction:
Refer to part (a).
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Chemistry: Principles and Practice
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