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Chemistry Homework Help => AP Chemistry => Topic started by: Siddharth_Pendyala on April 29, 2025, 02:29:54 PM

Title: Thermochemistry MCQ: Which Reaction Transfers the Most Heat to the Surroundings?
Post by: Siddharth_Pendyala on April 29, 2025, 02:29:54 PM
Hi, I was confused on two questions I got wrong from the quiz 6.1. Could you please explain how to solve these?
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Title: Re: 6.1 Quiz Problems
Post by: uma on January 20, 2026, 09:33:23 AM
Quote from: Siddharth_Pendyala on April 29, 2025, 02:29:54 PMHi, I was confused on two questions I got wrong from the quiz 6.1. Could you please explain how to solve these?
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Correct answer: a. All of the lost heat is gained by the surroundings.
As the pressure increases, a gas in a non-rigid container can change its volume to match the external pressure. If the gas expands, it does PV work on the surroundings.Work is also the form of energy so all this energy is gained by the surroundings.
So, when the system "loses energy," it can lose it as heat and/or work, but any heat that leaves the system goes to the surroundings
Title: Re: 6.1 Quiz Problems
Post by: uma on January 20, 2026, 09:45:36 AM
Quote from: Siddharth_Pendyala on April 29, 2025, 02:29:54 PMHi, I was confused on two questions I got wrong from the quiz 6.1. Could you please explain how to solve these?

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The right answer is the reaction between a strong acid and a strong base (HCl + NaOH). Since both fully ionize in water, the reaction is essentially H⁺ + OH⁻ → H₂O and goes to completion, producing the maximum heat release (largest heat transfer from the system to the surroundings).