Crystallization

RESULTS

Unknown Code Number:

salicylamide; mp observed literature mp

benzamide; mp observed literature mp

benzoic acid; mp observed literature mp

mp of unknown mixture

Table

Solvent

~ml solvent

g of unknown

g collected

% recovered

mp of crystals

water 

 

 

 

 

 

ethanol:water 75:25

 

 

 

 

 

 

Identity of Recovered Material:

 

DISCUSSION

Describe the process of crystallization in general. What is happening on a molecular level?

Why does recrystallization result in a purification of the solid? Where did the "impurity" go?

Discuss the selection of a good solvent for crystallization.

Describe your observations during the experiment. What did you see? How long did it take for crystals to form? What did they look like?

Compare the results from the two crystallization solvents. Which one worked best? Did you recover a larger amount of crystals? Was the melting point higher? Why? Why did the one work less well? BE SURE your results support your statements here.

What was the identity of the main component of your unknown sample? In what percent was it present? How well do you think you were able to recover the main component? Was any left behind in the filtrate?