Atomic hydrogen (H) is used in welding (AHW). The atoms recombine to hydrogen molecules with a large release of heat according to the following reaction: 2 H(g) → H 2 (g) (a) Using the thermodynamic data in Appendix C, calculate the enthalpy change for this reaction per mole of H 2 .

Hey everyone. So we have sofa try outside gas reacting with water to produce sulfuric acid. When asked about the balanced equation, calculate the standard and to be changed for the reaction. So for sulfur dioxide gas we're gonna have s. 0. 3 gas And then water which is H. 20. Like when And this is going to you know sulfuric acid which is H S. 04 A quiz. So this is balanced. And for our standard entropy change recall that the entropy of the reaction is a song of the number of malls kinds of entropy information of the products minuses some times the number of moles time to entropy information of the reactant till the end of your information of sulfur trioxide. It's negative 3 95 point to kill jules promote and Anthony information of sulfuric acid Is negative 0.3 Phil jones promote and interview information of water. This may go to 85 .8 kg promote for the independent their reaction we're gonna have the entropy of the formation of sulfuric acid minus the entropy information of sulfur trioxide as the entropy of formation of water. So the entropy of the reaction Is -909.3 still does promote -395 0.2. Still just from all -285 .8 kg promote the entropy of the reaction. 228 0.3. Hello jules. Thanks for watching my video and I hope it was up for

Ch.5 - Thermochemistry

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Brown 14th Edition

Ch.5 - Thermochemistry

Problem 41a

Chapter 5, Problem 41a

Atomic hydrogen (H) is used in welding (AHW). The atoms recombine to hydrogen molecules with a large release of heat according to the following reaction: 2 H(g) → H₂(g) (a) Using the thermodynamic data in Appendix C, calculate the enthalpy change for this reaction per mole of H₂.

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Identify the reaction: 2 H(g) → H₂(g). This reaction involves the recombination of two hydrogen atoms to form one hydrogen molecule.

Consult Appendix C for the standard enthalpy of formation (ΔH_f°) values. Note that the standard enthalpy of formation for any element in its most stable form, such as H₂(g), is zero.

Recognize that the enthalpy change for the reaction (ΔH_rxn) can be calculated using the formula: ΔH_rxn = ΣΔH_f°(products) - ΣΔH_f°(reactants).

Since the product is H₂(g) with ΔH_f° = 0 and the reactant is 2 H(g), use the given thermodynamic data to find the ΔH_f° for H(g).

Substitute the values into the formula: ΔH_rxn = [1 * ΔH_f°(H₂(g))] - [2 * ΔH_f°(H(g))] to calculate the enthalpy change per mole of H₂ formed.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Enthalpy Change

Enthalpy change (ΔH) is a measure of the heat content of a system at constant pressure. It indicates the amount of energy absorbed or released during a chemical reaction. For the reaction given, calculating ΔH involves determining the difference in enthalpy between the products (H2) and the reactants (2 H). This value is crucial for understanding the energy dynamics of the reaction.

Thermodynamic Data

Thermodynamic data, often found in tables or appendices, provides essential information such as standard enthalpies of formation, which are necessary for calculating the enthalpy change of reactions. These values represent the energy change when one mole of a compound is formed from its elements in their standard states. Utilizing this data allows for accurate calculations of ΔH for the reaction in question.

Mole Concept

The mole concept is a fundamental principle in chemistry that relates the amount of substance to its mass and the number of particles it contains. In this context, it is important to understand that the enthalpy change calculated should be expressed per mole of H2 produced. This ensures that the results are standardized and can be compared across different reactions and conditions.

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Mole Concept

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Atomic hydrogen (H) is used in welding (AHW). The atoms recombine to hydrogen molecules with a large release of heat according to the following reaction: 2 H(g) → H2(g) (a) Using the thermodynamic data in Appendix C, calculate the enthalpy change for this reaction per mole of H2.

Verified video answer for a similar problem:

Key Concepts

Enthalpy Change

Thermodynamic Data

Mole Concept

Atomic hydrogen (H) is used in welding (AHW). The atoms recombine to hydrogen molecules with a large release of heat according to the following reaction: 2 H(g) → H₂(g) (a) Using the thermodynamic data in Appendix C, calculate the enthalpy change for this reaction per mole of H₂.