Geometry around Bonded Carbon Atoms

When all four bonds to a carbon are single bonds, there are four regions of high electron density and the geometry around this carbon is tetrahedral. The molecular geometry of compounds containing just one carbon (as the central atom) is therefore tetrahedral. Examples of this are methane (CH4) and carbon tetrachloride (CCI4). These molecules would appear as shown with the 

FIGURE 14.3 A drawing of the ball-and-stick model showing the tetrahedral molecular geometry exemplified by such molecules as CH4 and CCI4. The sticks in such models represent single bonds (a pair of electrons being shared). 

FIGURE 14.4 Photographs of three actual ball-and-stick models showing how a carbon chain forms. From left, methane, ethane, and propane. Notice the tetrahedral geometry around each of the carbons. 

FIGURE 14.5 Ball-and-stick models (hydrogens removed) of carbon chains that are three, four, five, and six carbons long. The sawtooth appearance is due to the tetrahedral geometry around carbons where there are only single bonds attached. 

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The geometry around all carbon atoms is tetrahedral, and all bond angles are approximately 109°. 

Structural representations of the hydrocarbon ethane are shown in Figure 20.2. To how many other atoms is each carbon atom bonded in ethane What is the geometry around each carbon atom in ethane ... 

Four bonds adopt a tetrahedral geometry around the carbon atom. 

When heated, azodicarbonamide breaks apart into gaseous carbon monoxide, nitrogen, and ammonia. Azodicarbonamide is used as a foaming agent in the polymer indushy. (a) Add nonbonding electron pairs and multiple bonds as required to complete the Lewis stmcture of this molecule, (b) Determine the geometry around each inner atom. 

In this hybridized state the carbon will make two single bonds and one double bond. This will allow the carbon atom to bond to three different atoms. The orientation of these atoms around the carbon atom will be trigonal planar molecular geometry. The angle of these atoms to one another is 120 degrees. This is demonstrated in the diagram of ethene shown in Figure 3.11. 

The geometric arrangement of atoms around each carbon atom in ethane is tetrahedral. All bond angles are 109.5° as predicted from the geometry. ... 

Each carbon has two bonds, a C—H single bond and a C=C triple bond, so two electron clouds are around each carbon atom. Linear geometry places two electron clouds as far as possible from each other. In ethyne, the four atoms are arranged in a straight line, so ethyne is a linear molecule. 

Hydrocarbons that contain at least one C=C bond are called alkynes (general formula C H2 2). Because a carbon in a C=C bond can bond to only one other atom, the geometry around each C atom is linear (180°) each C is ip hybridized. Alkynes are named in the same way as alkenes, except that the suffix is -yne. Because of their localized it electrons, C=C and C=C bonds are electron rich and act as functional groups. Thus, alkenes and alkynes are much more reactive than alkanes, as we ll discuss in Section 15.4. 

However, ds and trans isomers are not possible for alkynes because the geometry around the triple-bond carbon atoms is linear. 

A, and the C(carbene)-0 distance of 1.431 A is similar to that of a C-0 single bond and much longer than the distance of ca. 1.33 A observed in mononuclear carbene complexes. In further contrast to mononuclear carbene complexes, the carbene group is not strictly planar the carbene carbon atom is displaced by 0.197 A from the best plane through the Fe(tetracarbonyl), C(carbene), C(phenyl), and O(OEt) atoms. Nevertheless, the geometry around carbene-carbon is much closer to tri nal planar than to tetrahedral. 

When carbon forms a double bond and two single bonds, there are three electron groups around each carbon atom, and VSEPR theory predicts a trigonal planar geometry. 

When carbon forms a triple bond and a single bond (or two double bonds), there are two electron groups around each carbon atom, resulting in a linear geometry. 

When carbon forms four single bonds, they are arranged tetrahedrally around the carbon atom the molecular geometry is tetrahedral (Fig. 21.1). Recall from Chapter 13 that it is not possible to represent this three-dimensional shape accurately in a two-dimensional sketch. Thus the four bonds radiating from each carbon atom in... 

What is the bond angle around a carbon atom with four single bonds What word describes this geometry ... 

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