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Ch.8 - Basic Concepts of Chemical Bonding
Brown - Chemistry: The Central Science 14th Edition
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232Not the one you use?Change textbook
All textbooksBrown 14th EditionCh.8 - Basic Concepts of Chemical BondingProblem 102
Chapter 8, Problem 102

One scale for electronegativity is based on the concept that the electronegativity of any atom is proportional to the ionization energy of the atom minus its electron affinity: electronegativity = k(I - EA), where k is a proportionality constant. (d) Use your result from part (c) to determine the electronegativities of Cl and O using this scale. (e) Another scale for electronegativity defines electronegativity as the average of an atom’s first ionization energy and its electron affinity. Using this scale, calculate the electronegativities for the halogens, and scale them so that fluorine has an electronegativity of 4.0. On this scale, what is Br’s electronegativity?

Verified step by step guidance
1
To determine the electronegativities of Cl and O using the first scale, use the formula: χ=k(I-EA), where I is the ionization energy and EA is the electron affinity. Substitute the values for Cl and O into this equation.
For the second scale, calculate the electronegativity using the formula: χ=I+EA2. This gives the average of the ionization energy and electron affinity for each halogen.
To scale the electronegativities so that fluorine has a value of 4.0, determine the scaling factor by dividing 4.0 by the calculated electronegativity of fluorine using the second scale.
Apply the scaling factor to the calculated electronegativities of each halogen to adjust them to the new scale where fluorine is 4.0.
Finally, use the adjusted electronegativity value for bromine to determine its electronegativity on the new scale.

Key Concepts

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

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons when forming chemical bonds. It is a key concept in understanding how atoms interact in molecules, influencing bond polarity and molecular structure. Different scales exist to quantify electronegativity, with values often ranging from 0 to 4, where higher values indicate a stronger attraction for electrons.
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Ionization Energy

Ionization energy is the energy required to remove an electron from an isolated atom in its gaseous state. It reflects how tightly an atom holds onto its electrons; higher ionization energy indicates a stronger hold. This property is crucial for determining an atom's electronegativity, as it directly influences the atom's ability to attract additional electrons.
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Electron Affinity

Electron affinity is the amount of energy released when an electron is added to a neutral atom in the gas phase. It indicates how much an atom 'wants' to gain an electron, with more negative values signifying a greater tendency to accept an electron. This concept is essential for calculating electronegativity, as it complements ionization energy in determining an atom's overall electron-attracting ability.
Related Practice
Textbook Question

Acetylene (C2H2) and nitrogen (N2) both contain a triple bond, but they differ greatly in their chemical properties. (b) By referring to Appendix C, look up the enthalpies of formation of acetylene and nitrogen. Which compound is more stable?

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Textbook Question

(c) Hydrogen peroxide is sold commercially as an aqueous solution in brown bottles to protect it from light. Calculate the longest wavelength of light that has sufficient energy to break the weakest bond in hydrogen peroxide.

Textbook Question

Consider the molecule C4H5N, which has the connectivity shown below. (a) After the Lewis structure for the molecule is completed, how many s and how many p bonds are there in this molecule?

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Textbook Question

The Ti2+ ion is isoelectronic with the Ca atom. (c) What charge would Ti have to be isoelectronic with Ca2+ ?

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Textbook Question

One scale for electronegativity is based on the concept that the electronegativity of any atom is proportional to the ionization energy of the atom minus its electron affinity: electronegativity = k1I - EA2, where k is a proportionality constant. (b) Why are both ionization energy and electron affinity relevant to the notion of electronegativity?

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