(c) For a given process at constant pressure, _x001F_H is negative. Is the process endothermic or exothermic?

Name: Chemistry: The Central Science
Author: Brown
ISBN: 9780134414232

검증된 단계별 안내

Step 1: Understand the terms 'endothermic' and 'exothermic'. An endothermic process absorbs heat from the surroundings, while an exothermic process releases heat to the surroundings.

Step 2: Recognize that the symbol ΔH represents the change in enthalpy, which is the heat change at constant pressure.

Step 3: Note that a negative ΔH indicates that the system is losing heat to the surroundings.

Step 4: Connect the concept of a negative ΔH with the definition of an exothermic process, which is characterized by the release of heat.

Step 5: Conclude that if ΔH is negative, the process is exothermic, as it involves the release of heat to the surroundings.

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Enthalpy Change (_x001F_H)

Enthalpy change (_x001F_H) is a measure of the heat absorbed or released during a chemical reaction or physical process at constant pressure. A negative _x001F_H indicates that the system releases heat to the surroundings, which is a key characteristic of exothermic processes.

Exothermic vs. Endothermic Processes

Exothermic processes are those that release energy, usually in the form of heat, to the surroundings, resulting in a temperature increase in the environment. In contrast, endothermic processes absorb energy from the surroundings, leading to a temperature decrease. The sign of the enthalpy change helps determine the nature of the process.

Constant Pressure Conditions

Constant pressure conditions are often encountered in chemical reactions occurring in open systems, where the pressure remains stable throughout the process. Under these conditions, the enthalpy change is directly related to the heat exchanged, making it easier to classify the reaction as either exothermic or endothermic based on the sign of _x001F_H.