What purpose does the addition of finely divided charcoal serve during the recrystallization of impure acetanilide?

This is follow up from the previous question:  Compare the major differences in terms of the specific properties each technique (that you just described above), capitalizes on 

Why is it dangerous to heat a liquid in a distilling apparatus that is closed tightly at every joint and has no vent to the atmosphere ?

Unknown A has a melting point of 89.0 o C.  Unknown B has a melting point of 91.0 o C.  However, they look the same – Explain how you would differentiate(tell if they are the same or different) between A and B .  Be thorough in your response

First, all students should check to make sure my computer is formatted to complete coursework in the most efficient manner. If students experience a technical problem using Honorlock, they should contact __________ to figure out and resolve the problem.  

Which of the following is NOT a reason as to why plagiarism is considered to be wrong?

DaNea is studying ethnocentrism.  What is the definition of the term?

John is presenting his informative speech.  When keeping his goal in mind, he should do all of the following EXCEPT:  

All of the following are true of audiences EXCEPT:

Josey is writing her outline for her informative speech over self-improvement practices.  She realizes that her speech’s thesis and her specific purpose differ in three specific ways.  Which of the following is NOT one of the three ways that a thesis differs from the specific purpose?