In a double bond, which type of bond is formed by the overlap of $p$ orbitals?

For the following partial structures, the σ bond is shown. Add the indicated number of π bonds, being sure to specify the orientation (that is, x, y, or z axis) of the p orbitals used.

(e)

The molecular orbital picture of H₂ can be represented by the following diagram. Label σ and σ* on the diagram—that is, which is (a) and which is (b)? Which is lower in energy? Why?

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Given the Lewis structures, indicate the direction of the dipole moment, if there is one.

(e)

How many s bond orbitals are available for overlap with the vacant p orbital in

1. the isobutyl cation?

2. the n-butyl cation?

3. the sec-butyl cation?

In the formation of $\sigma$ and $\pi$ bonds, which type of electrons are primarily involved?

What type of chemical bond is formed when two sulfur-containing chains are joined together?

In the context of molecular interactions, what type of bond is typically broken when $mRNA$ separates from the $DNA$ template during transcription?

Alpha-helices and beta-pleated sheets are formed by hydrogen bonds between which of the following components?