Facebook Facebook Twitter Twitter. Updated February 13, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Properties of Ionic and Covalent Compounds. What Is the Most Electronegative Element? Clickable Periodic Table of the Elements. Metals Versus Nonmetals - Comparing Properties. Metallic Character: Properties and Trends. Periodic Table Definition in Chemistry.
Data taken from John Emsley, The Elements , 3rd edition. Oxford: Clarendon Press, Electronegativity refers to the ability of an atom to attract shared electrons in a covalent bond. The higher the value of the electronegativity, the more strongly that element attracts the shared electrons. The concept of electronegativity was introduced by Linus Pauling in ; on the Pauling scale, fluorine is assigned an electronegativity of 3.
Other electronegativity scales include the Mulliken scale, proposed by Robert S. Mulliken in , in which the first ionization energy and electron affinity are averaged together, and the Allred-Rochow scale, which measures the electrostatic attraction between the nucleus of an atom and its valence electrons. Explanation: This table gives us a color-coded visualization of the trends for electronegativity on the periodic table. Why is this the trend?
Related questions How did Pauling define electronegativity? What is the difference between electronegativity and electron affinity? What is the definition of electronegativity? What trends in electronegativity occur in a period? Question 4c Which group of elements is listed in order of increasing electronegativity?
Nevertheless, when different methods for measuring the electronegativity of an atom are compared, they all tend to assign similar relative values to a given element. For example, all scales predict that fluorine has the highest electronegativity and cesium the lowest of the stable elements, which suggests that all the methods are measuring the same fundamental property.
Electronegativity is defined as the ability of an atom in a particular molecule to attract electrons to itself. The greater the value, the greater the attractiveness for electrons. Both of these are properties of the isolated atom.
An element will be highly electronegative if it has a large negative electron affinity and a high ionization energy always endothermic, or positive for neutral atoms. Thus, it will attract electrons from other atoms and resist having its own electrons attracted away. The original electronegativity scale, developed in the s by Linus Pauling — was based on measurements of the strengths of covalent bonds between different elements.
Pauling arbitrarily set the electronegativity of fluorine at 4. Because electronegativities generally increase diagonally from the lower left to the upper right of the periodic table, elements lying on diagonal lines running from upper left to lower right tend to have comparable values e. Values for most of the actinides are approximate.
Elements for which no data are available are shown in gray. Source: Data from L. Pauling, The Nature of the Chemical Bond , 3rd ed.
Linus Pauling is the only person to have received two unshared individual Nobel Prizes: one for chemistry in for his work on the nature of chemical bonds and one for peace in for his opposition to weapons of mass destruction. He developed many of the theories and concepts that are foundational to our current understanding of chemistry, including electronegativity and resonance structures.
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