CHMA11H3 Lecture Notes - Lecture 2: Stoichiometry, Paramagnetism, Linear Combination Of Atomic Orbitals

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CHMA11H3 Full Course Notes

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Apply schr dinger"s wave equation to the molecule to calculate a set of molecular orbitals. Starts with good guesses from experience of what the orbital should look like. Then test and tweak the estimate until the energy of the orbital is minimized. In this treatment, the electrons belong to the whole molecule and therefore the orbitals belong to the whole molecule. Electron density located outside the internuclear axis. Electrons in antibonding orbitals cancel stability gained by electrons in bonding orbitals. The simplest guess starts with the atomic orbitals of the atoms adding together to make molecular orbitals. Orbitals are wave functions thus the waves combine either constructively or destructively. Crest + crest makes a super crest (attraction) Trough + trough makes a super trough (repulsion) When the wave functions combine constructively, the resulting molecular orbital has less energy than the original atomic orbitals. This is called a bonding molecular orbital. Most of the electron density between the nuclei.

Related Questions

Which of the following statements relating to Molecular Orbital (MO) Theory is incorrect?

Combination of two 2p orbitals may result in either sigma() or pi() MOs.
A species with a bond order of zero will not be stable.
In a stable molecule having an even number of electrons, all electrons must be paired.
Combination of two atomic orbitals produces one bonding and one antibonding MO.
A bonding MO is lower in energy than the two atomic orbitals from which it is formed.

jadeelk940

Benzene is an organic chemical compound with the molecular formula C6H6. In the benzene molecule, carbon atoms form a ring with alternating single and double bonds connecting them. Thus, each individual carbon atom forms one ? bond with another carbon atom and one ? and one ? bond with another carbon atom. Each carbon atom also forms one ? bond with a hydrogen atom. Identify which types of orbitals overlap to form the bonds between the atoms in a benzene molecule. Drag the appropriate labels to their respective targets.

Attached is picture. Please explain/show work, will give 5 stars to correct answer, thank you very much! :)

Chemical bonds are formed by linear combinations of atomic orbital's. These atomic orbital's should have compatible energies. An axial overlap of these orbitals results in the formation of a sigma bond, whereas a lateral overlap results in the formation of a pi bond. When two atomic orbitai's on different atoms approach each other, two molecular orbital's are formed: one bonding molecular orbital and one antibonding molecular orbital. The bonding molecular orbital has a lower energy than the corresponding atomic orbital's: antibonding orbital's have higher energies than the corresponding atomic orbital's. An example using the hydrogen molecule is shown here. However, the same rule applies to systems with multiple atomic orbital's. For each atomic orbital that overlaps, one molecular orbital must form. In the diagram below. 1s orbitais from two hydrogen atoms combine to form one bonding sigma1 orbital and one antibonding orbital. The total number of bonding and antibonding orbital's is always equal to the number of orbital's that overlap. Similarly, molecular orbital's can also be formed by the overlapping of hybrid orbital's. The hybrid orbital's are formed by the linear combination of different atomic orbital's of nearly equal energy on the same atom. The atomic orbital's of nearly equal energy undergo a process of mixing and reorientation to form new orbital's of lower energy. This process is called hybridization For example, hybridization of one s and two p orbital's on an atom forms three sp2 hybrid orbital's. Benzene is an organic chemical compound with the molecular formula C6H6. In the benzene molecule, carbon atoms form a ring with alternating single and double bonds connecting them. Thus, each individual carbon atom forms one sigma bond with another carbon atom and one sigma and one pi bond with another carbon atom. Each carbon atom also forms one sigma bond with a hydrogen atom. Identify which types of orbital's overlap to form the bonds between the atoms in a benzene molecule.

CHMA11H3 Lecture Notes - Lecture 2: Stoichiometry, Paramagnetism, Linear Combination Of Atomic Orbitals

CHMA11H3 Full Course Notes

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