Lewis structures hydrogen fluoride

Representing a two electron covalent bond by a dash (—) the Lewis structures for hydrogen fluoride fluorine methane and carbon tetrafluoride become... 

Due to its strong hydrogen bonds, in the vapor state hydrogen fluoride is found as short chains and rings. Draw the Lewis structure of an (HF)3 chain and indicate the approximate bond angles. 

The Lewis structure of hydrogen fluoride shows three lone pairs on the fluorine atom. These nonbonding electrons are localized in atomic orbitals that belong solely to fluorine. Remembering that one of the fluorine 2 p orbitals is used to form the H—F bond, we conclude that the three lone pairs must occupy the remaining pair 2 p orbitals and the 2 s orbital of the fluorine atom. 

Let us consider the hydrogen fluoride (HF) molecule as a simple example. The conventional Lewis structure diagram of this molecule... 

For hydrogen fluoride, which is well described by a single Lewis structure (cf. Example 1.6), the localized natural Lewis-structure model wavefunction gives... 

Individual atoms of hydrogen and fluorine are highly reactive, and readily bond together to form molecules of hydrogen fluoride. Draw a Lewis structure for hydrogen fluoride. Label the bonding and lone pairs, and explain why this molecule is stable. 

Combine H- and -F to give the Lewis structure for hydrogen fluoride H F ... 

In order to obtain octets of electrons, these atoms tend to form compounds in which they have one bond and three lone pairs. Note how the Lewis structures of hydrogen fluoride, HF (used in the refining of uranium), hydrogen bromide, FiBr (a pharmaceutical intermediate), and hydrogen iodide, Fil (used to make iodine salts) resemble the structure of hydrogen chloride. 

In Section 9.3 we learned that hydrogen fluoride is a covalent molecule with a polar bond. There is a shift of electron density from H to F because the F atom is more electronegative than the H atom. The shift of electron density is symbolized by placing a crossed arrow (H—above the Lewis structure to indicate the direction of the shift. For example,... 

Lewis Structure of a Molecule The pattern on the glass shown in Figure 8.6 was made by chemically etching its surface with hydrogen fluoride (HF). Draw the Lewis structure for a molecule of hydrogen fluoride. 

Electron pair donors and acceptors Consider the reaction between a hydrogen ion (H+) and a fluoride ion (F ) to form a hydrogen fluoride (HF) molecule. The role of the electron pair is illustrated through the following Lewis structures. 

The electrons in a bond between two identical atoms, such as that present in H2, can be considered to be equally shared between both of them. If the atoms are not identical, however, the electrons may be more attracted to one atom than the other. For example in hydrogen fluoride, HF, the Lewis structure might be more accurately written as... 

Alkenes are also sources of carbonium ions for alkylations. Protic acids— especially sulfuric acid, phosphoric acid, and hydrogen fluoride—and Lewis acids, such as BF3 and AIQ3, are used as catalysts. " Insofar as comparisons have been made, such factors as position selectivity and tendency toward isomerism of the alkyl group to more stable structures are similar to those described with alkyl halides as alkylating agents. ... 

We know from Chapter 7 that representing electrons with dots, as we do in the Lewis model, is a drastic oversimplification. As we have already discussed, this does not invah-date the Lewis model—which is an extremely useful theory— but we must recognize and compensate for its inherent limitations. One limitation of representing electrons as dots, and covalent bonds as two dots shared between two atoms, is that the shared electrons always appear to be equally shared. Such is not the case. For example, consider the Lewis structure of hydrogen fluoride ... 

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