(a) Interpretation: The value of Δ H ° for the given reaction is to be calculated. Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH° . Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Question

Want to see more full solutions like this?

Answer 1

Question

Formula Formula Bond dissociation energy (BDE) is the energy required to break a bond, making it an endothermic process. BDE is calculated for a particular bond and therefore consists of fragments such as radicals since it undergoes homolytic bond cleavage. For the homolysis of a X-Y molecule, the energy of bond dissociation is calculated as the difference in the total enthalpy of formation for the reactants and products. X-Y → X + Y BDE = Δ H f X + Δ H f Y – Δ H f X-Y where, ΔHf is the heat of formation.

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Students have asked these similar questions

Consider the reactionsN2H4(l) + CH4O(l) → CH2O(g) + N2(g) + 3H2(g) ΔH = 80 kJ/molN2(g) + 3 H2(g) → 2 NH3(g) ΔH = −91.8 kJ/molCH4O(l) → CH2O(g) + H2(g) ΔH = 130.6 kJ/molWhat is the ΔH for the over all reaction shown below in kJ/mol?

10. Calculate AH for the reaction CH4 (g) + NH3 (g) → HCN (g) + 3 H2 (g), given: AH = -91. 8 kJ AH = -74. 9 kJ AH = +270. 3 k] a. N2 (g) + 3 H2 (g) → 2 NH3 (g) b. C (s) + 2 H2 (g) → CH4 (g) c. H2 (g) + 2 C (s) + N2 (g) → 2 HCN (g)

Calculate ΔHo for attached reaction. Classify each reaction as endothermic or exothermic.

Answer 2

Question

Formula Formula Bond dissociation energy (BDE) is the energy required to break a bond, making it an endothermic process. BDE is calculated for a particular bond and therefore consists of fragments such as radicals since it undergoes homolytic bond cleavage. For the homolysis of a X-Y molecule, the energy of bond dissociation is calculated as the difference in the total enthalpy of formation for the reactants and products. X-Y → X + Y BDE = Δ H f X + Δ H f Y – Δ H f X-Y where, ΔHf is the heat of formation.

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 3

Question

Formula Formula Bond dissociation energy (BDE) is the energy required to break a bond, making it an endothermic process. BDE is calculated for a particular bond and therefore consists of fragments such as radicals since it undergoes homolytic bond cleavage. For the homolysis of a X-Y molecule, the energy of bond dissociation is calculated as the difference in the total enthalpy of formation for the reactants and products. X-Y → X + Y BDE = Δ H f X + Δ H f Y – Δ H f X-Y where, ΔHf is the heat of formation.

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 4

Question

Formula Formula Bond dissociation energy (BDE) is the energy required to break a bond, making it an endothermic process. BDE is calculated for a particular bond and therefore consists of fragments such as radicals since it undergoes homolytic bond cleavage. For the homolysis of a X-Y molecule, the energy of bond dissociation is calculated as the difference in the total enthalpy of formation for the reactants and products. X-Y → X + Y BDE = Δ H f X + Δ H f Y – Δ H f X-Y where, ΔHf is the heat of formation.

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Answer 6

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −51 kJ/mol.

Answer 7

Chapter 6, Problem 6.32P

Interpretation Introduction

(a)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reaction. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Answer 8

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −51 kJ/mol.

Answer 9

Expert Solution

Answer 10

Expert Solution

Answer 11

Expert Solution

Answer 12

Explanation of Solution

The chemical equation for the given reaction is,

H3C−CH3+Br−Br→H3C−CH2−Br+HBr

The bond dissociation energy of CH2−H, and Br−Br bond is 410 kJ/mol and 192 kJ/mol and CH2−Br is 285 kJ/mol and H−Br is 368 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(410 kJ/mol+192 kJ/mol)+((−285 kJ/mol)+ (−368 kJ/mol))=−51 kJ/mol

Therefore, the value of ΔH° is −51 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Answer 13

Conclusion

The value of ΔH° is −51 kJ/mol.

Answer 14

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Conclusion

The value of ΔH° is −63 kJ/mol.

Answer 15

Interpretation Introduction

(b)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Answer 16

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −63 kJ/mol.

Answer 17

Expert Solution

Answer 18

Expert Solution

Answer 19

Expert Solution

Answer 20

Explanation of Solution

The chemical equation for the given reaction is,

HO⋅+CH4→⋅CH3+H2O

The bond dissociation energy of CH3−H, and H−OH bond is 435 kJ/mol and 498 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−498 kJ/mol)=−63 kJ/mol

Therefore, the value of ΔH° is −63 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is released during the reaction.

Answer 21

Conclusion

The value of ΔH° is −63 kJ/mol.

Answer 22

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Conclusion

The value of ΔH° is −34 kJ/mol.

Answer 23

Interpretation Introduction

(c)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Answer 24

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is −34 kJ/mol.

Answer 25

Expert Solution

Answer 26

Expert Solution

Answer 27

Expert Solution

Answer 28

Explanation of Solution

The given reaction is,

CH3OH+HBr→CH3Br+H2O

The bond dissociation energy of CH3−OH, H−Br, CH3−Br and H−OH is 389 kJ/mol, 368 kJ/mol, 293 kJ/mol and 498 kJ/mol respectively.

The bonds broken in the reactants are CH3−OH and H−Br, whereas the bonds formed in the products are CH3−Br and H−OH.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(389 kJ/mol+368 kJ/mol)+(−293 kJ/mol−498 kJ/mol)=757 kJ/mol−791 kJ/mol=−34 kJ/mol

Therefore, the value of ΔH° is −34 kJ/mol. The negative sign indicates that the given reaction is an exothermic reaction and the energy is release during the reaction.

Answer 29

Conclusion

The value of ΔH° is −34 kJ/mol.

Answer 30

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.

Conclusion

The value of ΔH° is +142 kJ/mol.

Answer 31

Interpretation Introduction

(d)

Interpretation: The value of ΔH° for the given reaction is to be calculated.

Concept introduction: The chemical reaction in which energy is released during the formation of products is known as exothermic reactions. The energy released during the reaction is denoted by ΔH°. Exothermic and endothermic reactions are opposite to each other. The value of ΔH° for exothermic and endothermic reactions is positive and negative respectively.

Answer 32

Expert Solution

Answer to Problem 6.32P

The value of ΔH° is +142 kJ/mol.

Answer 33

Expert Solution

Answer 34

Expert Solution

Answer 35

Expert Solution

Answer 36

Explanation of Solution

The given reaction is,

Br⋅+CH4→⋅H+CH3−Br

The bond dissociation energy of CH3−H, and CH3−Br bond is 435 kJ/mol and 293 kJ/mol respectively.

The overall enthalpy change in the chemical reaction is calculated by the formula,

ΔH°=Sum of ΔH° of bonds broken+Sum of ΔH° of bonds formed

Substitute the values of ΔH° of bonds broken and ΔH° of bonds formed in the above expression.

ΔH°=(435 kJ/mol)+(−293 kJ/mol)=+142 kJ/mol

Therefore, the value of ΔH° is +142 kJ/mol. The positive sign indicates that the given reaction is an endothermic reaction and the energy is absorbed during the reaction.