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Ch.15 - Chemical Equilibrium
McMurry - Chemistry 8th Edition
McMurry8th EditionChemistryISBN: 9781292336145당신이 사용하는 게 아니라요?교과서 변경
15장, 문제 129

For the following reaction catalyzed by iridium, which is endothermic at 700 K: CaO(s) + CH₄(g) + 2 H₂O(g) ⇌ CaCO₃(s) + 4 H₂(g), how would the following changes affect the total quantity of CaCO₃ in the reaction mixture once equilibrium is reestablished at 700 K? (a) Increasing the temperature (b) Adding calcium oxide (c) Removing methane (CH₄) (d) Adding iridium.

검증된 단계별 안내
1
Step 1: Understand the nature of the reaction. The reaction is endothermic, meaning it absorbs heat. According to Le Chatelier's principle, increasing the temperature will favor the endothermic direction, which is the forward reaction in this case, increasing the amount of CaCO₃.
Step 2: Consider the effect of adding calcium oxide (CaO). Adding a reactant will shift the equilibrium to the right, towards the products, to counteract the change, thus increasing the amount of CaCO₃.
Step 3: Analyze the impact of removing methane (CH₄). Removing a reactant will shift the equilibrium to the left, towards the reactants, to replace the removed substance, thus decreasing the amount of CaCO₃.
Step 4: Evaluate the role of adding iridium. Iridium is a catalyst, which speeds up the rate at which equilibrium is reached but does not affect the position of the equilibrium. Therefore, adding iridium will not change the amount of CaCO₃ at equilibrium.
Step 5: Summarize the effects: (a) Increasing temperature increases CaCO₃, (b) Adding CaO increases CaCO₃, (c) Removing CH₄ decreases CaCO₃, (d) Adding iridium has no effect on CaCO₃ at equilibrium.

주요 개념

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

Le Chatelier's Principle

Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract the change. This principle helps predict how a system at equilibrium will respond to changes in concentration, temperature, or pressure, thereby affecting the amounts of reactants and products present.
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07:32
Le Chatelier's Principle

Endothermic Reactions

An endothermic reaction is one that absorbs heat from its surroundings. In the context of the given reaction, increasing the temperature will favor the formation of products, as the system will shift to absorb the added heat, thus potentially increasing the quantity of CaCO₃ produced at equilibrium.
추천 영상:
가이드 코스
02:30
Endothermic & Exothermic Reactions

Catalysts and Equilibrium

A catalyst, such as iridium in this reaction, speeds up the rate of both the forward and reverse reactions without being consumed. While it helps the system reach equilibrium faster, it does not affect the position of equilibrium or the total quantities of reactants and products at equilibrium.
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가이드 코스
02:35
Thermal Equilibrium