Final answer:
For compounds with closer boiling points, fractional distillation is better compared to simple distillation due to increased efficiency in separation. Factors affecting boiling points include molecular mass and polarity, with nonpolar compounds' boiling points mainly influenced by London dispersion forces.
Step-by-step explanation:
For compounds with closer boiling points, fractional distillation is more effective compared to simple distillation. The process involves a distillation setup with a fractionating column that increases the surface area for repeated vaporization-condensation cycles.
As a result, the separation of compounds with close boiling points becomes more efficient, leading to a purer distillate. This method is particularly useful when refining crude petroleum into numerous products, such as gasoline and diesel fuel, or distilling alcoholic spirits like brandy.
When analyzing boiling points, factors like molecular mass and polarity are considered. Higher molecular mass and polarity often result in higher boiling points. For nonpolar compounds, such as alkanes, London dispersion forces dictate boiling points, with larger molecules generally having higher boiling points due to increased dispersion forces, like in the sequence C₂H₆ < C₃H₈ < C₄H₁₀.