When H2 and CO2 react, acetic acid can be formed spontaneously while the production of formaldehyde requires an input of energy. Which of these conclusions can be drawn from this observation? a. More heat is released when formaldehyde is produced compared to the production of acetic acid. b.Compared to the reactants that it is formed from, formaldehyde has more potential energy than does acetic acid. c. Entropy decreases when acetic acid is produced and increases when formaldehyde is produced. d. Only acetic acid could be produced under conditions that existed in early Earth.

Verified step by step guidance

1. Identify the key reaction: Acetic acid forms spontaneously, while formaldehyde formation requires energy input.
2. Analyze spontaneity: A spontaneous reaction indicates that the products have lower potential energy than the reactants, implying acetic acid has lower potential energy than the reactants.
3. Evaluate potential energy: If formaldehyde requires energy input to form, it must have higher potential energy than its reactants, unlike acetic acid.
4. Consider entropy: Acetic acid forms without energy input, typically associated with an increase in entropy, while energy input for formaldehyde suggests a decrease in entropy.
5. Draw conclusion: Since formaldehyde has more potential energy than acetic acid, the correct answer is b.

Key Concepts

Spontaneous Reactions

A spontaneous reaction is one that occurs without the need for external energy input, typically because it leads to a decrease in free energy. In the context of the question, the formation of acetic acid from H2 and CO2 is spontaneous, indicating that the products are more stable than the reactants, and the reaction releases energy, often in the form of heat.

Potential Energy in Chemical Reactions

Potential energy in chemical reactions refers to the energy stored in the chemical bonds of molecules. When comparing acetic acid and formaldehyde, the observation that formaldehyde requires energy input suggests it has higher potential energy than acetic acid, meaning it is less stable and more reactive under the given conditions.

Entropy and Thermodynamics

Entropy is a measure of disorder or randomness in a system, and according to the second law of thermodynamics, the total entropy of an isolated system can never decrease over time. In the reactions mentioned, the production of acetic acid may involve a decrease in entropy due to the formation of a more ordered structure, while the production of formaldehyde may increase entropy, reflecting a more chaotic arrangement of molecules.