For an endothermic chemical reaction, how does the enthalpy of the reaction products compare with that of the initial reactants?
Answer and explanation
Correct answer: D. the products have higher enthalpy than reactants, and ΔH is positive
- Step 1: In an endothermic process, thermal energy is absorbed from surroundings: ΔH = H_products - H_reactants > 0. Step 2. Therefore, H_products > H_reactants (the enthalpy of products is greater). Answer: the products have higher enthalpy than reactants, and ΔH is positive. Why not the others: Lower product enthalpy with negative ΔH defines exothermic reactions; identical enthalpy implies no reaction; enthalpy does not drop to zero.
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