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Ch.18 - Free Energy and Thermodynamics
Tro - Chemistry: A Molecular Approach 4th Edition
Tro4th EditionChemistry: A Molecular ApproachISBN: 9780134112831당신이 사용하는 게 아니라요?교과서 변경
18장, 문제 44

Calculate the change in Gibbs free energy for each of the sets of ΔHrxn, ΔSrxn, and T given in Problem 42. Predict whether or not each reaction is spontaneous at the temperature indicated. (Assume that all reactants and products are in their standard states.)

검증된 단계별 안내
1
Identify the formula for Gibbs free energy change: \( \Delta G = \Delta H - T \Delta S \).
Substitute the given values for \( \Delta H \), \( \Delta S \), and \( T \) into the formula.
Ensure that the units are consistent, typically converting \( \Delta S \) from J/mol·K to kJ/mol·K by dividing by 1000.
Calculate \( \Delta G \) using the substituted values.
Determine spontaneity: if \( \Delta G < 0 \), the reaction is spontaneous; if \( \Delta G > 0 \), it is non-spontaneous.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m

주요 개념

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

Gibbs Free Energy (G)

Gibbs free energy is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. It is defined by the equation G = H - TS, where H is enthalpy, T is temperature, and S is entropy. A negative change in Gibbs free energy (ΔG < 0) indicates that a reaction is spontaneous, while a positive change (ΔG > 0) suggests non-spontaneity.
추천 영상:
가이드 코스
01:51
Gibbs Free Energy of Reactions

Enthalpy (ΔH)

Enthalpy is a measure of the total heat content of a system and is used to quantify the energy changes during chemical reactions. The change in enthalpy (ΔH) can be either positive or negative, indicating whether a reaction absorbs heat (endothermic, ΔH > 0) or releases heat (exothermic, ΔH < 0). This value is crucial for determining the spontaneity of a reaction when combined with entropy changes.
추천 영상:
가이드 코스
02:34
Enthalpy of Formation

Entropy (ΔS)

Entropy is a measure of the disorder or randomness in a system. The change in entropy (ΔS) during a reaction reflects how the distribution of energy changes, with positive ΔS indicating increased disorder and negative ΔS indicating decreased disorder. In the context of Gibbs free energy, a positive ΔS can favor spontaneity, especially at higher temperatures, as it contributes to a more negative ΔG.
추천 영상:
가이드 코스
02:46
Entropy in Thermodynamics