Bond length and strength

[Lauren Bui 1E]

What is the relationship between bond length and bond strength? and is there a reason for this relationship?

[Vanessa Chuang 4F]

Basically the longer the bond length, the weaker the bond strength is. Conversely, the shorter the bond length is, the stronger the bond strength. The closer two atoms are to one another, the more strongly bound they are, meaning it becomes harder to break apart the bond and vice versa.

[Ryan Narisma 4G]

Hi Lauren Bui 1E! To answer your question, bond length and bond strength are inversely proportional—that is: if the bond length is longer, the bond strength is weaker and if the bond length is shorter, then the bond strength is stronger. Bond length corresponds to the internuclear distance between two bonding atoms (i.e. the nucleus-nucleus distance). When more electrons are shared between atoms (i.e. 2 or 3 covalently bonded atoms), the electrostatic attraction between the shared electrons and the nuclei increases and therefore the pull is much more stronger. Because both nuclei are pulling onto the electrons more strongly, the distance between these two atoms decreases. Therefore, as you increase the number of bonds between two atoms, the internuclear distance between these atoms decreases. Thus, the bond length decreases when you increase the number of shared electrons because the electrostatic attractions between the shared electrons and the nuclei of the atoms increases. I hope this helps!

[Karina Kong 2H]

There are also less lone pair electrons that make that pull the atoms away from each other when there are more bonds. Therefore, more bonds correlates with higher strength.