英语翻译The students' understanding of the reaction mechanisms d

英语翻译
The students' understanding of the reaction mechanisms depends on when the experiment is performed in relation to the coverage of course topics.The author and his colleagues have performed the experiment before the introduction of electro-
philic aromatic substitution or enolate halogenation in lectures.However,by the time the students' reports were due,the former topic had been discussed in the classroom,and students under-stood that the chlorination was an example of an electrophilic aromatic substitution.
Besides being used in the second-semester organic labora- tory,this experiment is also appropriate as an early experiment of an advanced or third-semester organic laboratory.Because the reactions are operationally simple,the instructor can emphasize the opportunity for students to become (re)acquainted with the hands-on operation of several instruments.In addition,the experiment reinforces the concepts of reactivity,selectivity,and spectral interpretation that were introduced in the second- semester organic course.