20
Prelab Week 7 worksheet (hold on to until week 7). Complete and bring to lab with you.
This is part of your prelab grade.
components
d.
upper layer
c.
upper layer
a.
e.
b.
d.
lower layer
lower layer
f.
g.
Procedure for Experiment: “Extraction, Part D Optional”: Separation of a neutral compound
from a mixture containing a basic impurity.
Measure out ____ g of an unknown mixture containing a
compound.
1. Add this solid and
Mix completely.
2. Add
mL of
mL of
compound and a neutral
to a screw top centrifuge tube.
to the tube and mix thoroughly. Removed the
layer with a pipette to a labeled test tube.
3. Repeat step 3.
4. Add
M
to the removed layers in the test tube dropwise until a ppt.
forms. The identity of the ppt. is
.
5. To the
remaining in the centrifuge tube, add
mL of
and mix thoroughly. Remove the
layer to a labeled “holding” test
tube for later disposal.
6. Transfer the
Add
layer, remaining in the centrifuge tube, to a clean, dry test tube.
to remove the remaining water, wait
minutes.
7. Remove the liquid,
containing dissolved
to a clean,
tared container. Evaporate the solvent in the hood (don’t overheat). Determine the
mass and melting point of the solid remaining.