[Daily Question] Registered Exam Version 2020.07.19

Thread Content

This post was last edited by asdf2016 on 2020-7-21 08:54. The current questions are all taken from the professional foundation review textbooks published by Tianjin University Press; they are intended for students’ use and provided solely for reference. The decomposition reaction of substance A is a first-order reaction. Its initial concentration is cA,0 = 0.2 mol/dm3, and 20% of this initial concentration has decomposed. Then the required time t = ( ) minutes. A.60 B.6.93 C.360.86 D.50 The *answer* is: D. Feel free to engage in active discussions. 3 wealth for correct answers, 1 wealth for incorrect answers; 5 wealth for those who can provide the solution process and give the correct answer. Mass posting of posts – rated based on the lowest score ； Replies that are unrelated to the answer are considered spam and will be deleted immediately.