Final answer:
The chemical reaction is typically exothermic because it involves the formation of new bonds that release energy, although the exact nature of the reaction's enthalpy change would require specific bond energy calculations.
Step-by-step explanation:
The chemical reaction in question is C2H5Cl + Cl2 → C2H4Cl2 + HCl. To determine if the reaction is exothermic or endothermic, we consider the bond enthalpies of the reactants and products. Bond breaking requires energy and is an endothermic process, whereas bond formation releases energy, making it an exothermic process. Whether a reaction is overall exothermic or endothermic depends on the net energy change of breaking bonds in reactants and forming new bonds in products.
If the bonds in the products are stronger than those in the reactants, the reaction releases more energy than it absorbs, which makes it exothermic. Conversely, if the bonds in the products are weaker, the reaction is endothermic, as it absorbs more energy than it releases. For example, the combustion of methane, CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) + 213 kcal, is exothermic because it releases heat.
The reaction stated in the question (C2H5Cl + Cl2 → C2H4Cl2 + HCl) is typically exothermic as it involves the formation of HCl, which releases a significant amount of energy, although the full enthalpy change would depend on the specific bond energies of all reactants and products.