CHEM101 Lecture Notes - Lecture 8: Valence Bond Theory, Covalent Bond, Sigma Bond

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jadecicada397

30 Oct 2018

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Document Summary

Covalent bonds are formed by the overlap of valence atomic orbitals . Resulting in the electron density being concentrated between the two atoms connected. Only one pair of electrons can be shared by 2 overlapping atomic orbitals. 1s orbital contain only one electron, overlap of two 1s orbitals on two hydrogen atoms created a covalent bond, hence the electron density is concentrated between the two atomic nuclei. Hence the potential energy and the distance of the two atoms can be shown as. A covalent bond is formed end to end due to the overall of the 1s orbital and the half. F= 1s2 2s2 2px 2 2py 2 2pz 1. Covalent bond formed end to end overlapping by the singularly occupied 2pz orbitals in each atom. N=1s2 2s2 2px 1 2py 12pz 1. Overlap of 2pz orbitals gives a sigma bond in the nitrogen atoms ( )

Related Questions

(a) Using only the valence atomic orbitals of a hydrogen atom and a fluorine atom, and following the model of Figure 9.46, how many MOs would you expect for the HF molecule? (b) How many of the MOs from part (a) would be occupied by electrons? (c) It turns out that the difference in energies between the valence atomic orbitals of H and F are sufficiently different that we can neglect the interaction of the 1s orbital of hydrogen with the 2s orbital of fluorine. The 1s orbital of hydrogen will mix only with one 2p orbital of fluorine. Draw pictures showing the proper orientation of all three 2p orbitals on F interacting with a 1s orbital on H. Which of the 2p orbitals can actually make a bond with a 1s orbital, assuming that the atoms lie on the z-axis? (d) In the most accepted picture of HF, all the other atomic orbitals on fluorine move over at the same energy into the molecular orbital energy-level diagram for HF. These are called “nonbonding orbitals.” Sketch the energy-level diagram for HF using this information and calculate the bond order. (Nonbonding electrons do not contribute to bond order.) (e) Look at the Lewis structure for HF. Where are the nonbonding electrons?