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Ch.18 - Thermodynamics: Entropy, Free Energy & Equilibrium
McMurry - Chemistry 8th Edition
McMurry8th EditionChemistryISBN: 9781292336145당신이 사용하는 게 아니라요?교과서 변경
18장, 문제 35

The following pictures represent equilibrium mixtures for the interconversion of A molecules (red) and X, Y, or Z molecules (blue):Three cases showing equilibrium mixtures of A (green) with X, Y, Z (yellow) for Gibbs Free Energy analysis.
What is the sign of ∆G° for each of the three reactions?

검증된 단계별 안내
1
Identify the equilibrium mixtures for each case: Case 1 (B ⇌ X), Case 2 (B ⇌ Y), and Case 3 (B ⇌ Z).
Count the number of green (A) and yellow (X, Y, Z) molecules in each case to determine the equilibrium position.
Compare the number of reactant (A) and product (X, Y, Z) molecules to determine the direction of the reaction at equilibrium.
Use the relationship between the equilibrium position and Gibbs Free Energy (ΔG°) to determine the sign of ΔG°: if the reaction favors products, ΔG° is negative; if it favors reactants, ΔG° is positive.
Analyze each case: Case 1 has more green (A) than yellow (X), Case 2 has an equal number of green (A) and yellow (Y), and Case 3 has more yellow (Z) than green (A).

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 (∆G) is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. A negative ∆G indicates that a reaction is spontaneous, while a positive ∆G suggests non-spontaneity. The sign of ∆G is crucial for predicting the direction of a chemical reaction and its equilibrium position.
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가이드 코스
01:51
Gibbs Free Energy of Reactions

Equilibrium Constant (K)

The equilibrium constant (K) quantifies the ratio of the concentrations of products to reactants at equilibrium for a given reaction. It is related to the Gibbs Free Energy change by the equation ∆G° = -RT ln(K), where R is the gas constant and T is the temperature in Kelvin. A larger K value (greater than 1) indicates a reaction that favors products, while a smaller K value (less than 1) favors reactants.
추천 영상:
가이드 코스
01:14
Equilibrium Constant K

Reaction Quotient (Q)

The reaction quotient (Q) is a measure of the relative amounts of products and reactants present in a reaction at any point in time. It is calculated using the same formula as the equilibrium constant but with the current concentrations. Comparing Q to K helps determine the direction in which a reaction will proceed to reach equilibrium: if Q < K, the reaction will shift towards products, and if Q > K, it will shift towards reactants.
추천 영상:
가이드 코스
00:49
Reaction Quotient Q