(a)
Interpretation:
Whether the reaction is exothermic or endothermic when ΔH, i.e., change of enthalpy is positive needs to be explained.
Concept Introduction:
The change in enthalpy is defined as the difference in energy needed to break new bonds and the formation of new bonds. The pressure is considered constant in the process. These reactions can be endothermic or exothermic. In endothermic reaction, energy is required to form the products and in exothermic reaction, energy is released in the formation of products.
(b)
Interpretation:
Whether the reaction is exothermic or endothermic when the energy of the products is lower than the energy of reactants needs to be determined.
Concept Introduction:
In an endothermic reaction, energy is required whereas in exothermic reactions, energy is released.
(c)
Interpretation:
Whether the reaction is exothermic or endothermic when the energy is released in the reaction needs to be determined.
Concept Introduction:
In an endothermic reaction, energy is required whereas in exothermic reactions, energy is released.
(d)
Interpretation:
Whether the reaction is exothermic or endothermic if the bonds in reactants are stronger than the bonds in products needs to be determined.
Concept Introduction:
The change in enthalpy is defined as the difference in energy needed to break new bonds and the formation of new bonds. The pressure is considered constant in the process. These reactions can be endothermic or exothermic. In endothermic reaction, energy is required to form the products and in exothermic reaction, energy is released in the formation of products.
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General, Organic, and Biological Chemistry - 4th edition
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