Chapter 13, Problem 13.58QP

(a)

Interpretation Introduction

To determine: If the given reaction is either an exothermic or an endothermic reaction.

Interpretation: The given reaction is to be categorized as being an endothermic or an exothermic reaction.

Concept introduction: The values of enthalpy give information about the spontaneity and stability of the products. The value of Gibbs free energy depends upon the enthalpy. Enthalpy of the reaction is calculated by the formula,

$\Delta H_{\text{rxn}}^{°}=\Delta H_{\text{Products}}^{°}-\Delta H_{\text{Reactants}}^{°}$

(b)

Interpretation Introduction

To determine: if the carbon atom in calcium carbide is oxidized or reduced in the given reaction.

Interpretation: The carbon atom of calcium carbide in the given reaction is to be categorized as being oxidized or reduced.

Concept introduction: Redox reaction consists of oxidation and reduction reactions. In oxidation reactions, loss of electrons takes place and occurs at anode. In reduction reactions, gain of electrons takes place and occurs at cathode.