★Specialized Examination for Chemical Engineering ★ — One question per day (2015-11-23) — Points are awarded for participation

Thread Content

This post was last edited by zshiwei2008 on 2015-11-24 08:26. Points system for the daily question: Participation – 1~3 points; Correct answer – 5 points; In-depth analysis – 5~10 points. The answer is provided the next day. Daily Question (2015-11-23): 1. Regarding the concept of the drift factor in diffusion mass transfer, which of the following statements is correct? A. The drift factor is always greater than or equal to 1. B. The drift factor represents the ratio of the molecular diffusion rate to the rate of mass transfer due to unidirectional molecular diffusion. C. The concept of the drift factor applies only to processes of molecular diffusion-based mass transfer, not to convective mass transfer processes. D. The concept of the drift factor applies only to gas-phase diffusion-based mass transfer, not to liquid-phase diffusion-based mass transfer. Answer: The concept of the drift factor is related to the topics covered in the chapters on mass transfer mechanisms and absorption rates in chemical engineering principles; it is used when one component diffuses through another. The concept p/pBm is somewhat abstract, and questions related to mass transfer mechanisms are rarely asked in exams. The correct answer is A