Lab report for Experiment #2: Extraction
Your Name: Name of TA:
Lab Partner’s Name: Lab Section:
Title: Experiment #2: Extraction
Observations:
Weighed out 3.2568 grams of chemical mixture that was
yellow in color.
Dissolved dry chemicals in 38 ml CH2Cl2 with gentle heating.
Poured the yellow solution into sep funnel. Added 10 ml
CH2Cl2 to flask to rinse, poured solution into sep funnel.
Added 15 ml 3 M HCl, gently mixed and vented (saw bubbles
during mixing, heard the evolution of gas while venting).
Allowed layers to separate. Upper layer determined to be
aqueous by density: lower layer removed. Upper layer placed
into separate flask labeled “A” for acid extract. Lower
layer placed into sep. funnel and reextracted with 15 ml 3
M HCl. Combined aqueous layers in flask A
Reextracted CH2Cl2 layer containg chemicals with 15 ml 3 M
NaOH. Upper layer in flask labeled “B” for base extract.
Re-extract organic layer with 15 ml 3M NaOH. Combined base
extracted materials in flask “B”. Saw bubbles during
mixing, heard the evolution of gas while venting.
Dried organic layer with anhyd. Na2SO4 until free flowing
salt was observed (about 3 grams). Filtered the organic
solution into a tared 100 ml round-bottom flask. Rinsed
flask and funnel with 10 ml of CH2Cl2 and rotovaped off
remaining solvent and weighed flask. The biphenyl obtained
was white in color and was like a powder.
Weight of flask and biphenyl = 106.1784 g
Weight of empty flask = 104.7368 g
Weight of recovered biphenyl = 1.4416
Cooled flask A in a water bath. Added 18 ml 6 M NaOH and
pH tested. Still acidic, litmus paper was red. Added 1.5
ml more 6 M NaOH; and the alkaline solution became cloudy
and pH paper turned blue. Yellow crystals were seen to
form. Cooled in ice bath for 21 minutes. Collected p-
nitroaniline (yellow crystals)using vacuum filtration.
Washed with cold water and allowed to dry for 12 minutes
Dry solid p-nitroaniline and watch glass = 18.9372 g
