Mass transfer co-efficient of liquid is

ANS:A - affected more by temperature than that for gases.

The mass transfer coefficient of a liquid is generally affected more by temperature than that for gases. Explanation:

1. Temperature Effect:
   • In mass transfer processes involving liquids, temperature variations can significantly influence the mass transfer coefficient.
   • Generally, an increase in temperature leads to an increase in the mass transfer coefficient for liquid-phase mass transfer.
   • This increase in mass transfer coefficient with temperature is often attributed to the enhanced diffusivity of solute molecules in the liquid phase at higher temperatures.
   • Higher temperatures typically result in increased molecular mobility and diffusion rates within the liquid, facilitating faster mass transfer.
2. Gases vs. Liquids:
   • While temperature also affects the mass transfer coefficient in gas-phase mass transfer, the effect may not be as pronounced as in liquid-phase mass transfer.
   • In gas-phase mass transfer, temperature primarily influences the diffusion coefficients of gases in the gas phase, which can affect the overall mass transfer rate.
   • However, the influence of temperature on gas-phase mass transfer coefficients may be relatively smaller compared to its impact on liquid-phase mass transfer coefficients.
3. Mechanism Differences:
   • The mechanisms governing mass transfer in liquids and gases are different. In liquids, mass transfer often occurs primarily through molecular diffusion, while in gases, additional factors such as convection may play a significant role.
   • The predominance of molecular diffusion in liquid-phase mass transfer makes the process more sensitive to temperature changes, as diffusion rates are directly influenced by temperature.
4. Conclusion:
   • Overall, the mass transfer coefficient of a liquid is generally affected more by temperature variations compared to that for gases.
   • The temperature dependence of the mass transfer coefficient in liquids underscores the importance of considering temperature effects in the design and optimization of liquid-phase mass transfer processes.