Q1: Plate efficiency

ANS:A - is a function of the mass transfer between liquid and vapour.

Plate efficiency is a measure of the effectiveness of mass transfer between the liquid and vapor phases in a distillation column. It is typically defined as the ratio of the actual number of theoretical stages to the ideal number of theoretical stages required for a given separation. Higher plate efficiency indicates better separation performance. Therefore, the correct statement is: Plate efficiency is a function of the mass transfer between liquid and vapor. Efficient mass transfer between the liquid and vapor phases is crucial for achieving high plate efficiency in a distillation column. This involves promoting intimate contact between the phases to facilitate the transfer of components from one phase to the other, leading to improved separation efficiency. Factors such as column design, operating conditions, and the properties of the components being separated all influence the effectiveness of mass transfer and, consequently, plate efficiency. The other statements, which suggest that plate efficiency increases due to foaming, liquid entrainment, or weeping and dumping of liquid, are incorrect. These phenomena can actually decrease plate efficiency by disrupting the desired flow patterns and reducing the effectiveness of mass transfer in the column. Foaming, liquid entrainment, and weeping are often undesirable occurrences in distillation processes that operators seek to minimize to achieve optimal separation performance.