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Ch.19 - Free Energy & Thermodynamics
Tro - Chemistry: A Molecular Approach 5th Edition
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371당신이 사용하는 게 아니라요?교과서 변경
19장, 문제 95

All the oxides of nitrogen have positive values of ΔG°f at 298 K, but only one common oxide of nitrogen has a positive ΔS°f. Identify that oxide of nitrogen without reference to thermodynamic data and explain.

검증된 단계별 안내
1
Identify the common oxides of nitrogen: NO, NO2, N2O, N2O3, N2O4, and N2O5.
Understand that ΔS°_f refers to the standard entropy of formation, which is related to the disorder or randomness of a substance.
Consider the molecular structure and physical state of each oxide. Gases generally have higher entropy than solids or liquids due to greater molecular motion.
Recognize that N2O (dinitrogen monoxide) is a gas and has a relatively simple molecular structure, which contributes to a higher entropy compared to other nitrogen oxides that may be more complex or exist in different states.
Conclude that N2O is the oxide of nitrogen with a positive ΔS°_f due to its gaseous state and simple molecular structure, leading to higher entropy.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m

주요 개념

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

Gibbs Free Energy (ΔGf°)

Gibbs Free Energy (ΔGf°) is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. A positive ΔGf° indicates that the formation of the compound from its elements is non-spontaneous under standard conditions. Understanding this concept is crucial for analyzing the stability and reactivity of chemical species, particularly in the context of nitrogen oxides.
추천 영상:
가이드 코스
01:51
Gibbs Free Energy of Reactions

Entropy (ΔS°f)

Entropy (ΔS°f) is a measure of the disorder or randomness in a system. A positive ΔS°f suggests that the formation of the compound increases the overall disorder of the system, which is often associated with the production of gases or the breaking of strong intermolecular forces. Recognizing how entropy influences the spontaneity of reactions helps in identifying which nitrogen oxide exhibits this property.
추천 영상:
가이드 코스
02:46
Entropy in Thermodynamics

Nitrogen Oxides

Nitrogen oxides (NOx) are a group of gases that include various oxides of nitrogen, such as nitric oxide (NO) and nitrogen dioxide (NO2). Among these, nitrous oxide (N2O) is notable for having a positive ΔS°f, as it is a gas that contributes to increased disorder compared to its elemental forms. Understanding the characteristics and behaviors of these oxides is essential for identifying the specific oxide mentioned in the question.
추천 영상:
가이드 코스
01:30
Nitrogen Family Reactions