Final answer:
In cyclopropane, the least important strain type in determining the overall energy is steric strain. overall energy of cyclopropane. This is because cyclopropane has a small and highly strained ring, which makes angle and torsional strain dominant factors in determining its overall energy.
Step-by-step explanation:
In cyclopropane, the strain types that determine the overall energy are angle strain, torsional strain, and steric strain. Angle strain is the strain caused by bending the bond angles from the ideal tetrahedral bond angles, torsional strain is the strain caused by the eclipsing of hydrogen atoms on adjacent carbon atoms, while steric strain is caused by the repulsion between groups attached to non-adjacent ring atoms.
Out of these strain types, steric strain would be the least important in determining the overall energy of cyclopropane. This is because cyclopropane has a small and highly strained ring, which makes angle and torsional strain dominant factors in determining its overall energy.