Recrystallization Post-Lab Assignment
Organic Lab Techniques 1 (CHM2211L)
1.
Report collected data by completing the table below.
Mass of recrystallized NBS:
0.69 grams
Percent recovery:
69%
Melting point range:
175 °C to 177 °C
2.
Show the full calculation for the percent recovery that you reported in question 1.
massof recrystallized solid
massof crude
x
100
0.69
g NBS
1
g NBS
x
100
=
69%
NBS percent recovery
3.
Based on the data you reported, how pure is your recrystallized NBS?
Briefly
explain
your answer by comparing your experimental data (question 1) with the literature melting
point for NBS. According to the Recrystallization Pre-Lab Preparation video, we can compare our experimental melting point range to the literature (reported) melting point to know the purity and identity of the solid. NBS has a melting point range of 172 °C to 178 °C (
National Center for Biotechnology
Information). After evaluating both ranges, I can conclude that the resulting solid was more pure.
