bond angle strain

[504646485]

What exactly is a bond angle strain? And is cyclopropane the only molecule with bond angle strain?

[Bryce Bentley 1l]

Bond angle strain occurs when a molecule's bonds are not in their ideal positions. For a carbon atom bonded with four other atoms, the ideal shape tetrahedral with 109 degree angles. If the bonds are not at that exact degree, then there's bond angle strain. Cyclopropane, cyclobutane, cyclopentane, etc. have high bond angle strain when all the carbons are in the same plane.