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Ch.7 - Thermochemistry
Tro - Chemistry: A Molecular Approach 6th Edition
Tro6th EditionChemistry: A Molecular ApproachISBN: 9780137832217당신이 사용하는 게 아니라요?교과서 변경
7장, 문제 4

During an energy exchange, a chemical system absorbs energy from its surroundings. What is the sign of ΔEsys for this process?

검증된 단계별 안내
1
Identify the type of process: The problem states that the chemical system absorbs energy from its surroundings, which indicates an endothermic process.
Understand the concept of energy exchange: In an endothermic process, energy is absorbed by the system, meaning the system gains energy.
Determine the sign of \( \Delta E_{\text{sys}} \): Since the system is gaining energy, the change in energy of the system (\( \Delta E_{\text{sys}} \)) is positive.
Relate to the first law of thermodynamics: The first law states that energy cannot be created or destroyed, only transferred. Here, energy is transferred into the system, increasing its internal energy.
Conclude the sign of \( \Delta E_{\text{sys}} \): Therefore, the sign of \( \Delta E_{\text{sys}} \) is positive, indicating an increase in the system's energy.

주요 개념

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

Energy Exchange

Energy exchange in a chemical system refers to the transfer of energy between the system and its surroundings. This can occur in the form of heat or work, and it is crucial to understand how energy flows to determine the changes in the system's internal energy.
추천 영상:
가이드 코스
01:26
Nature of Energy

Internal Energy (ΔEsys)

The internal energy of a system, denoted as ΔEsys, represents the total energy contained within the system, including kinetic and potential energy of its particles. When a system absorbs energy, its internal energy increases, leading to a positive value for ΔEsys.
추천 영상:
가이드 코스
00:40
Internal Energy

Sign Convention in Thermodynamics

In thermodynamics, a sign convention is used to indicate the direction of energy transfer. If a system absorbs energy, it is considered positive, while energy released to the surroundings is negative. Thus, for a system absorbing energy, ΔEsys is positive.
추천 영상:
가이드 코스
01:18
First Law of Thermodynamics