Trigonal planar arrangement hybrid orbitals

A trigonal planar arrangement of orbitals indicates sp hybridization (steric number 3) however, the geometry may be bent, depending on the number of lone pairs. 

Answer Three cr-bonds formed from F2/7c-orbitals and B2s/r hybrids in a trigonal planar arrangement]... 

To minimise repulsion, the three sp hybrid orbitals adopt a trigonal planar arrangement, l.e. they lie in the same plane with an angle of 120° between them. 

Fig. 2.2. Several representations of ethylene, which has two bonded carbon atoms, (a) is a ball and stick model, (b) shows a chemical structure, and (c) is a schematic orbital diagram. Note the trigonal planar arrangement of the bonds between the atoms-this arrangement is the consequence of the hybrid orbital structure.

The central carbon atom has a trigonal planar arrangement of the electron pairs that requires sp hybridization. Two of the sp hybrid orbitals are used to form the two bonds to hydrogen. The other sp hybrid orbital forms the cr bond to oxygen. The unchanged (unhybridized) p orbital on carbon Is used to form the 7T bond between carbon and oxygen. 

In graphite, the carbon atoms are in a trigonal planar arrangement with each carbon bonded to three nearest neighbors. The carbon is sp hybridized. Hybridization occurs between the C 2s orbital and the 2p and 2p, orbitals producing three hybrid orbitals lying in a plane at 120° to each other. Overlap of the sp hybrid orbitals to produce localized bonds between carbon atoms results in a hexagonal network. 

Because carbon has four valence electrons ([He]2s 2p ), it forms four bonds in virtually all its compounds. When all four bonds are single bonds, the electron pairs are disposed in a tetrahedral arrangement. (Section 9.2) In the hybridization model, the carbon 2s and 2p orbitals are then sp hybridized. (Section 9.5) When there is one double bond, the arrangement is trigonal planar (sp hybridization). With a triple bond, it is linear (sp hybridization). Examples are shown in T FIGURE 24.1. 

There are three pairs of electrons around Al therefore, the electron pair arrangement is trigonal planar. We conclude that Al uses sp hybrid orbitals in bonding with I because s] orbitals have a trigonal planar arrangement (see Table 10.4). The orbital diagram of the ground-state Al atom is... 

When the central atom of a small compound has a steric number of 3, it will be sp hybridized. As an example, consider the structure of BF3. Boron has three valence electrons, each of which is used to form a bond. The result is three bonds and no lone pairs, giving a steric number of 3. The central boron atom therefore requires three orbitals, rather than four, and must be sp hybridized. Recall that y> -hybridized orbitals achieve maximal separation in a trigonal planar arrangement (Figure 1.40) trigonal because the boron is connected to three other atoms and planar because all atoms are found in the same plane (as opposed to trigonal pyramidal). 

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