# Separation by Extraction

Autor:   •  October 30, 2018  •  1,067 Words (5 Pages)  •  112 Views

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Compound

MW (g/mol)

Isolated

moles

% recovery

Crude Phenanthrene

178.23

1.602g

0.00899

80.1%

Benzoic acid

122.12

1.280g

0.0105

128%

p-chloroaniline

127.57

Recrystallized Phenanthrene

178.23

1.227g

0.0069

122%

Provide a physical description of your isolated compounds

Crude Phenanthrene: light yellow powder

Benzoic acid: pinky white shinny powder

Recrystallized Phenanthrene: pale white shinny powder

Yield Calculation for Benzoic acid.

Theoretical yield = (concentration by mass) × (volume used) = (1g/100mL) × (100mL) = 1.00g,

so % yield = (mass experimental yield/mass of theoretical yield)×100% = (1.280g/1.00g) ×100%= 128%

Note: during extraction of benzoic acid, the solution was contaminated so there was a yellow snowball-liked sediment. This might cause the mass experimental yield larger than the theoretical yield.

Yield Calculation for Crude of Phenanthrene

Theoretical yield = (concentration by mass) × (volume used) = (2g/100mL) × (100mL) = 2.00g,

so % yield = (mass experimental yield/mass of theoretical yield)×100% = (1.602g/2.00g) ×100%= 80.1%

Yield Calculation for Recrystallization of Phenanthrene

(Mass yielded/mass used)×100% = (1.227g/1.006g)×100% = 122%

Melting Range Data

Sample Determined

Observed Melting Range

Lit. Melting Range

Identification

Component from solution A

62-65

67-70

p-Chloroaniline

Component from solution B

90-95

121-123

Benzoic acid (but contaminated)

Crude phenanthrene

79-87

99-101

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Recrystallized phenanthrene

104-105

99-101

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The sample for the melting range of p-Chloroaniline was supplied by Toni Sikkema.

Solubility Data

Solubility

Compound

Ethanol

Hexanes

Toluene

Water

cold

hot

cold

hot

cold

hot

cold

Hot

Anthranilic acid

s

v

i

δ

i

v

δ

s

Phenanthrene

i

δ

i

v

v

i

i

Benzoic acid

δ

s

v

v

i

i

p-Chloroaniline

δ

s

i

s

v

i

δ

Abbreviations: i—insoluble, δ or sl—slightly soluble, s—soluble, v—very soluble.

Thin-layer Chromatography

Make a note of the conditions used to record the tlc (type of plate, solvent used and visualization method(s)). Attach your tlc plate (in the bag!) to the right of this table.

The tlc was ran on a 6.5cm strip of silica gel chromatogram plate. The solvent used was a 2:1 mixture of cyclohexane and ethyl acetate. The

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