"How does mass transfer affect the efficiency of distillation columns? Discuss the role of tray efficiency, interfacial area, and vapor$-$liquid equilibrium in determining separation efficiency. Explain how factors such as temperature, pressure, and flow rates influence mass transfer rates within the column. Additionally, analyze the impact of tray spacing and design on overall column performance. Provide examples of industrial applications where optimizing mass transfer processes in distillation columns is crucial for achieving desired separation outcomes."