Bond strength

[Molly Posta 1H]

Are pi-bonds always weaker than sigma-bonds, or is this dependent on molecular shape?

If this is true, is it also true that the sum of 2 single bonds of any homonuclear diatomic molecule will be stronger than one double bond of the same molecule? Or is this only true for certain elements like carbon?

[Kailani_Dial_2K]

pi bonds are alwys weaker than sigma bonds because sigma bonds have more overlap in the oorbitals than the pi bonds. For the second question you asked it applies to all molecules.

[Neha Jonnalagadda 2D]

Pi bonds are generally weaker covalent bonds than sigma bonds just because pi bonds have a smaller overlap between the orbital. However, combined, there is a larger overlap between the orbitals and that makes pi and sigma bonds combined stronger.

[AashaK]

Hi!

Pi bonds are weaker than sigma bonds. This is because the p-orbitals overlap in a side-by-side fashion, making the overlap smaller and weaker than the end-to-end overlap in a sigma bond. This explains why a one double bond is stronger than one single bond, but one double bond is weaker than the sum of three single bonds. The combination of multiple sigma bonds is stronger than one double bond. But the combination of a sigma and pi bond, is stronger than one sigma bond.

[Julia Zahra]

Pi bonds are always weaker cause they can't move.

[Joseph Liao 3C]

Since pi bonds bind two atoms together in two locations, as opposed to sigma bonds that only bind in one location, pi bonds are stronger. This makes sense, as the two binding sites also lock the atoms in place rotationally -- they are unable to rotate, unlike sigma bonds that allow them to.

[Lizzy Bulla 3K]

Pi bonds will always be generally weaker than sigma bonds because there is less overlap between the orbital

[Narin Maisha 2H]

Pi bonds are weaker than sigma bonds. This is because sigma bonds have more overlap, while pi-bonds only have side by side overlap. This means that a pi bond is weaker than a sigma bond, which also explains bond strength. A double bond which is made up of a sigma bond and a pi bond is stronger than a single sigma bond, but three sigma bonds are stronger than a double bond.

[Daniel Tabibian 3K]

A sigma bond will be stronger than a pi bond due to increased overlap of orbitals.

[Jessica Ghiuzelian 1H]

Hi! Pi bonds will always be weaker than sigma bonds because they are bonded side-by-side, meaning that they cannot rotate about the atom freely. If the pi bond is rotated, it would break.