BuyFindarrow_forward

Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
ISBN: 9781305079243

Solutions

Chapter
Section
BuyFindarrow_forward

Chemistry: An Atoms First Approach

2nd Edition
Steven S. Zumdahl + 1 other
ISBN: 9781305079243
Textbook Problem

The standard enthalpies of formation for S(g), F(g), SF4(g), and SF6(g) are +278.8, +79.0, −775, and +1209 KJ/mol, respectively.

a. Use these data to estimate the energy of an S—F bond.

b. Compare your calculated value to the value given in Table 3-3. What conclusions can you draw?

c. Why are the  Δ H f ° values for S(g) and F(g) not equal to zero, since sulfur and fluorine are elements?

(a)

Interpretation Introduction

Interpretation:

The S- F bond energy should be calculated and standard enthalpies of formation values of S(g) and F(g) should be explained.

Hess's Law:

Standard enthalpy of formation:

  • The change in enthalpy that associate with the formation of one mole of a product from its pure elements, with all substances in its standard states is called as a standard enthalpy of formation.
  • Formula:

    ΔHfnpΔH°f(products)-nrΔH°f(reactants)......(1)

  • Internal energy change of a reaction is given as,
  • Internal energy change ΔE= Bond broken energy - Bond formation energy

    ΔE=Dbroken-Dformed......(2)

  • The internal energy change is equal to enthalpy change in the gas phase reactions.
  • The dissociation bond energy is equal to enthalpy change in the gas phase reactions
Explanation

Record data from given:

Standard enthalpies of formation S(g)is+278.8kJ/molStandard enthalpies of formationF(g)is+79.0kJ/molStandard enthalpies of formationSF4(g)is-775kJ/molStandard enthalpies of formationSF6(g)is+1209kJ/mol

To calculate the SF bond energy in  SF .

SF4dissociationreaction:SF4(g)S(g)+4F(g)ΔH°=278.8+4(79.0)-(775)ΔH°=1370kJDSF=ΔH°NumberofS-FbondThis enthalpy change is equal to 4 ×(dissociation energySFbond).DSF=1370kJ4=342

(b)

Interpretation Introduction

Interpretation:

The S- F bond energy should be calculated and standard enthalpies of formation values of S(g) and F(g) should be explained.

Hess's Law:

Standard enthalpy of formation:

  • The change in enthalpy that associate with the formation of one mole of a product from its pure elements, with all substances in its standard states is called as a standard enthalpy of formation.
  • Formula:

    ΔHfnpΔH°f(products)-nrΔH°f(reactants)......(1)

  • Internal energy change of a reaction is given as,
  • Internal energy change ΔE= Bond broken energy - Bond formation energy

    ΔE=Dbroken-Dformed......(2)

  • The internal energy change is equal to enthalpy change in the gas phase reactions.
  • The dissociation bond energy is equal to enthalpy change in the gas phase reactions

(c)

Interpretation Introduction

Interpretation:

The S- F bond energy should be calculated and standard enthalpies of formation values of S(g) and F(g) should be explained.

Hess's Law:

Standard enthalpy of formation:

  • The change in enthalpy that associate with the formation of one mole of a product from its pure elements, with all substances in its standard states is called as a standard enthalpy of formation.
  • Formula:

    ΔHfnpΔH°f(products)-nrΔH°f(reactants)......(1)

  • Internal energy change of a reaction is given as,
  • Internal energy change ΔE= Bond broken energy - Bond formation energy

    ΔE=Dbroken-Dformed......(2)

  • The internal energy change is equal to enthalpy change in the gas phase reactions.
  • The dissociation bond energy is equal to enthalpy change in the gas phase reactions

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Additional Science Solutions

Find more solutions based on key concepts

Show solutions add

A person who is setting goals in preparation for a behavior change is in a stage called Precontemplation. T F

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

Calculate your protein RDA.

Understanding Nutrition (MindTap Course List)

Why is degenerate matter so difficult to compress?

Horizons: Exploring the Universe (MindTap Course List)

What are sister chromatids?

Human Heredity: Principles and Issues (MindTap Course List)

What is the maximum number of bonds that a carbon atom can form?

Biology: The Dynamic Science (MindTap Course List)

True or false? Most species that evolved have already become extinct.

Biology: The Unity and Diversity of Life (MindTap Course List)

In Figures 17.22a and 17.22b, notice that the amplitude of the component wave for frequency f is large, that fo...

Physics for Scientists and Engineers, Technology Update (No access codes included)