Acetylsalicylic AcidAcetylsalicylic Acid

By: Jeraun PogueBy: Jeraun PogueTierra DixonTierra Dixon

Chemistry llChemistry ll

Mrs. HallMrs. Hall

October 27,2008October 27,2008

AbstractAbstract

The study’s main objective was to find the purity aspirin throughout six different The study’s main objective was to find the purity aspirin throughout six different experiments. In Standardization of a Pipette, the experiments. In Standardization of a Pipette, the determine to calculate values that are determine to calculate values that are not measurable with the equipment provided. The average amount of drops per one mL was not measurable with the equipment provided. The average amount of drops per one mL was 18.33;there is 0.33 mL for every one drop. Synthesis of Aspirin lab showed how to make aspirin. 18.33;there is 0.33 mL for every one drop. Synthesis of Aspirin lab showed how to make aspirin. The lab Determination of Melting Point was used to get the melting point of each lab because The lab Determination of Melting Point was used to get the melting point of each lab because melting point shows aspirin purity. Several sample compounds were placed into a Mel-Temp melting point shows aspirin purity. Several sample compounds were placed into a Mel-Temp apparatus and melted a high temperatures. Relative Purity was also used to check chemical apparatus and melted a high temperatures. Relative Purity was also used to check chemical compounds color before and after they mixed with iron(III)chloride. Introduction to Digital compounds color before and after they mixed with iron(III)chloride. Introduction to Digital Spectrophotometer lab familiarized groups with the functions of the Spectrophotometer 20-D Spectrophotometer lab familiarized groups with the functions of the Spectrophotometer 20-D machine. Spectrophotometric Analysis of Aspirin lab purpose was to machine. Spectrophotometric Analysis of Aspirin lab purpose was to determine the amount determine the amount of aspirin in a commercial aspirin product. This lab may also be used to determine of aspirin in a commercial aspirin product. This lab may also be used to determine the purity of the aspirin produced in the Microscale Synthesis of Acetylsalicylic Acid the purity of the aspirin produced in the Microscale Synthesis of Acetylsalicylic Acid lab. lab. The overall conclusion to the study found was the Chemistry II sample aspirin was not pure. The chemicals used to make the samples were not pure either. the Chemistry IA and Chemistry IB sample aspirin was not pure either. The chemicals used in the making the aspirin were originally pure but mixed together they came out in an impure form. The standardization of a pipette was a cause for an impure result. Relative purity showed the impure state. Melting points showed the chemicals used in the making of the aspirin were impure.

History of AspirinHistory of Aspirin

Aspirin is used as a pain reliever and fever Aspirin is used as a pain reliever and fever depressant. It was originally made from depressant. It was originally made from willow bark extract but today is made from willow bark extract but today is made from salicylic acid (sodium calculate). salicylic acid (sodium calculate). Hippocrates was the first scientist to Hippocrates was the first scientist to prescribe bark tree leaves as a pain prescribe bark tree leaves as a pain reliever. A German scientist named Felix reliever. A German scientist named Felix Hoffman that lived in Bayer Germany was Hoffman that lived in Bayer Germany was the first person to stabilize acetylsalicylic the first person to stabilize acetylsalicylic acid when he used it to relieve his father’s acid when he used it to relieve his father’s rheumatism in 1897.rheumatism in 1897.

In 1828 the active ingredient in willow bark was isolated In 1828 the active ingredient in willow bark was isolated by Johann Buchner into a bitter tasting yellow needle-by Johann Buchner into a bitter tasting yellow needle-crystal form called salicin. Around 1920, aspirin was crystal form called salicin. Around 1920, aspirin was used to treat symptoms of pain related to rheumatism, used to treat symptoms of pain related to rheumatism, lumbago, and neuralgia. As years past aspirin history lumbago, and neuralgia. As years past aspirin history expanded. In 1988, aspirin became used as a potential expanded. In 1988, aspirin became used as a potential lifesaver; it was approved by the FDA to prevent mini-lifesaver; it was approved by the FDA to prevent mini-strokes in men and made standard therapy for previous strokes in men and made standard therapy for previous strokes in men. strokes in men.

History of AspirinHistory of Aspirin

Standardization of a Standardization of a PipettePipette The purpose of this experiment is to The purpose of this experiment is to

determine to calculate values that are determine to calculate values that are not measurable with the equipment not measurable with the equipment provided.provided.

DataData

Number of Drops per 1mLNumber of Drops per 1mL

Trial 1Trial 1 20 drops20 drops

Trial 2Trial 2 16 drops16 drops

Trial 3Trial 3 19 drops19 drops

Formula for Average # of drops per 1mL = T1 + T2 + T3

/ 3Average: __________18.33_____________Formula for # of mL per drop: 1 drop x 1mL

1 # of drops1 drop: __________0.33________mL

ResultsResults

The results in this experiment were not precise The results in this experiment were not precise due to a non-repeating pattern, such as, plus due to a non-repeating pattern, such as, plus or minus one. The numbers came out to plus or minus one. The numbers came out to plus three then plus one. The accepted value for three then plus one. The accepted value for this experiment is 20. the results: 20, 16,19 this experiment is 20. the results: 20, 16,19 came out to be 91.65% accurate with a came out to be 91.65% accurate with a random error of 8.35% because the results random error of 8.35% because the results were above and below the accepted value. To were above and below the accepted value. To improve the lab there should be a more improve the lab there should be a more accurate and precise counting of the droplets, accurate and precise counting of the droplets, and there should most likely be more test to and there should most likely be more test to make sure the results are as precise as make sure the results are as precise as possible. possible.

Synthesis of AspirinSynthesis of Aspirin

The purpose of this experiment is to The purpose of this experiment is to make aspirin that is equivalent to half make aspirin that is equivalent to half of an aspirin tablet. of an aspirin tablet.

DataData

Mass of salicylic acid usedMass of salicylic acid used0.9140.914 g g

Mass of filter paper Mass of filter paper and productand product0.1390.139 g g

Mass of filter paperMass of filter paper1.761.76 g g

Mass of product Mass of product after dryingafter drying0.8460.846 g g

ResultsResults

In synthesis of aspirin the conclusion formed In synthesis of aspirin the conclusion formed was that the product had 21.16% error being was that the product had 21.16% error being 78.84% accurate. The measurements 78.84% accurate. The measurements compared to the standard were precise but compared to the standard were precise but the results were not. The lab also had a the results were not. The lab also had a theoretical yield of 37.3%. Reasons the theoretical yield of 37.3%. Reasons the results were not precise could be that some results were not precise could be that some of the chemicals were still in the sample or of the chemicals were still in the sample or when the sample was vacuum packed some when the sample was vacuum packed some of the sample could have been absorbed. of the sample could have been absorbed. Also the sample could not have been fully Also the sample could not have been fully made.made.

Melting PointMelting Point

The purpose of this experiment is The purpose of this experiment is to determine the melting point of to determine the melting point of observed compounds because it observed compounds because it shows the purity of a compound. shows the purity of a compound.

Data for Melting PointData for Melting PointSample Sample CompoundsCompounds

Trail 1Trail 1

Observed Observed

Melting Melting Point/ Range Point/ Range

Trail 2Trail 2

Observed Observed

Melting Point/ Melting Point/ RangeRange

Trail 3Trail 3

Observed Observed

Melting Melting Point/ RangePoint/ Range

Average Average

(of all 3 (of all 3 Trails)Trails)

Observed Observed

Melting Melting Point/ RangePoint/ Range

PossiblePossible

ContaminanContaminantt

Acetylsalicylic Acetylsalicylic AcidAcid

140°C140°C 140°C140°C 140°C140°C 140°C140°C 4% increase4% increase

Unknown Unknown containmentcontainment

Salicylic AcidSalicylic Acid 168°C168°C 168°C168°C 168°C168°C 168°C168°C 9% increase 9% increase with an with an unknown unknown contaminant contaminant

Phosphoric AcidPhosphoric Acid 42.35°C42.35°C 42.35°C42.35°C 42.35°C42.35°C 42.35°C42.35°C StandardStandard

Data for Melting Point Data for Melting Point cont.cont.

Acetic Acetic AnhydrideAnhydride

-73°C-73°C -73°C-73°C -73°C-73°C -73°C-73°C StandardStandard

WaterWater 0°C0°C 0°C0°C 0°C0°C 0°C0°C StandardStandard

Chemistry II Chemistry II SampleSample

16.6°C16.6°C 16.6°C16.6°C 16.6°C16.6°C 16.6°C16.6°C StandardStandard

Chemistry I A Chemistry I A SampleSample

124°C124°C 124°C124°C 124°C124°C 124°C124°C Contaminated with Contaminated with acetylsalicylic acid, acetylsalicylic acid, salicylic acid, salicylic acid, phosphoric acid, and phosphoric acid, and acetic anhydride acetic anhydride

Chemistry I B Chemistry I B SampleSample

150°C150°C 150°C150°C 150°C150°C 150°C150°C Contaminated with Contaminated with acetylsalicylic acid, acetylsalicylic acid, salicylic acid, salicylic acid, phosphoric acid, and phosphoric acid, and acetic anhydride acetic anhydride

Data for Melting Point cont.Data for Melting Point cont.

Enteric Enteric AspirinAspirin

169°C169°C 169°C169°C 169°C169°C 169°C169°C Contaminated with Contaminated with acetylsalicylic acid, acetylsalicylic acid, salicylic acid, salicylic acid, phosphoric acid, phosphoric acid, and acetic and acetic anhydride anhydride

Acetic AcidAcetic Acid 16.6°C16.6°C 16.6°C16.6°C 16.6°C16.6°C 16.6°C16.6°C Contaminated with Contaminated with acetylsalicylic acid, acetylsalicylic acid, salicylic acid, salicylic acid, phosphoric acid, phosphoric acid, and acetic and acetic anhydride anhydride

Assured Assured AspirinAspirin

150°C150°C 150°C150°C 150°C150°C 150°C150°C Contaminated with Contaminated with acetylsalicylic acid, acetylsalicylic acid, salicylic acid, salicylic acid, phosphoric acid, phosphoric acid, and acetic and acetic anhydride anhydride

ResultsResults

The conclusion for melting points was that The conclusion for melting points was that acetylsalicylic acid had a temperature of 140*C acetylsalicylic acid had a temperature of 140*C this 4% increase had an unknown cause. this 4% increase had an unknown cause. Salicylic acid had temperature of 168*C this 9% Salicylic acid had temperature of 168*C this 9% had an unknown contaminant. Phosphoric acid had an unknown contaminant. Phosphoric acid was a standard because of its temperature was a standard because of its temperature 42.35*C. Acetic anhydride was a standard with a 42.35*C. Acetic anhydride was a standard with a -73*C temperature. Water was a standard with a -73*C temperature. Water was a standard with a 0*C temperature. Chemistry II sample aspirin 0*C temperature. Chemistry II sample aspirin was a standard with a temperature f 16.6*C. was a standard with a temperature f 16.6*C. Chemistry IA sample was Contaminated with Chemistry IA sample was Contaminated with acetylsalicylic acid, salicylic acid, phosphoric acetylsalicylic acid, salicylic acid, phosphoric acid, and acetic anhydride.acid, and acetic anhydride.

Relative PurityRelative Purity

The purpose of the this experiment The purpose of the this experiment is to check the purity of certain is to check the purity of certain such as: salicylic acid, assured such as: salicylic acid, assured aspirin, enteric aspirin, Chemistry IA aspirin, enteric aspirin, Chemistry IA sample aspirin, Chemistry IB sample aspirin, Chemistry IB sample aspirin, Chemistry II sample sample aspirin, Chemistry II sample aspirin, acetylsalicylic acid, acetic aspirin, acetylsalicylic acid, acetic anhydride, acetic acid, phosphoric anhydride, acetic acid, phosphoric acid.acid.

DataDataChemical Chemical compoundcompound

Color before Color before FeCl3FeCl3

Color after Color after FeCl3FeCl3

Salicylic acid Salicylic acid WhiteWhite Purple Purple

Assured Assured aspirin aspirin

WhiteWhite Clear Clear

Enteric Enteric aspirin aspirin

WhiteWhite Light pink Light pink

Chemistry IA Chemistry IA sample sample aspirin aspirin

WhiteWhite Yellow Yellow

Chemistry IB Chemistry IB sample sample aspirin aspirin

WhiteWhite Purple Purple

Data cont.Data cont.Chemistry II Chemistry II sample sample aspirin aspirin

WhiteWhite Yellow Yellow

Acetylsalicylic Acetylsalicylic acidacid

WhiteWhite Yellow Yellow

Acetic Acetic anhydride anhydride

ClearClear GoldGold

Acetic acid Acetic acid ClearClear OrangeOrange

Phosphoric Phosphoric acid acid

ClearClear ClearClear

ResultsResults The conclusion based on the results of the mixture of each of the ten The conclusion based on the results of the mixture of each of the ten

chemicals with Iron (III) chloride (FeCl3) was determined by each chemicals with Iron (III) chloride (FeCl3) was determined by each chemicals color after the mixture. If any of the chemicals are chemicals color after the mixture. If any of the chemicals are composed of six molecules of phenol combined with one Iron (III) ion composed of six molecules of phenol combined with one Iron (III) ion should produce a positive (purple) test with Iron (III) chloride. should produce a positive (purple) test with Iron (III) chloride. Salicylic acid and chemistry IB sample aspirin were originally white, Salicylic acid and chemistry IB sample aspirin were originally white, and then mixed with FeCl3 they turned purple meaning they and then mixed with FeCl3 they turned purple meaning they produced a positive test. Salicylic acid would be a standard because produced a positive test. Salicylic acid would be a standard because it was tested at its pure state and the chemistry IB sample aspirin it was tested at its pure state and the chemistry IB sample aspirin contains a high amount of salicylic acid. Chemistry IA sample aspirin, contains a high amount of salicylic acid. Chemistry IA sample aspirin, chemistry II sample aspirin, and acetylsalicylic acid were white and chemistry II sample aspirin, and acetylsalicylic acid were white and had yellow results meaning they were not positive. Acetylsalicylic had yellow results meaning they were not positive. Acetylsalicylic acid would be used be used as a standard and it would be known acid would be used be used as a standard and it would be known that that it can be found in the chemistry IA sample aspirin and that that it can be found in the chemistry IA sample aspirin and chemistry II sample aspirin. Acetic Anhydride was clear ending in a chemistry II sample aspirin. Acetic Anhydride was clear ending in a golden color being negative and a standard. Phosphoric acid was golden color being negative and a standard. Phosphoric acid was clear with clear results and it is also a standard meaning assured clear with clear results and it is also a standard meaning assured aspirin contains a large amount of phosphoric acid because of its aspirin contains a large amount of phosphoric acid because of its clear results. All the chemicals that turned out to be a standard were clear results. All the chemicals that turned out to be a standard were that way because when they were at their purest form. Mistakes that way because when they were at their purest form. Mistakes made would be adding to much FeCl3. Improvements to this lab made would be adding to much FeCl3. Improvements to this lab would be to be more precise with the amount the amount of would be to be more precise with the amount the amount of chemicals used and recorded. chemicals used and recorded.

Intro to Specs 20-DIntro to Specs 20-D

The purpose of the this The purpose of the this experiment is to familiarize you experiment is to familiarize you with the basic technology and with the basic technology and workings of the Spec-20D- how to workings of the Spec-20D- how to prepare a sample, which knob or prepare a sample, which knob or button does what, and how to button does what, and how to read and understand the display. read and understand the display.

DataData

ColorColor RedRed OrangOrangee

YelloYelloww

GreeGreenn

BlueBlue VioletViolet

WavelengtWavelengthh

630630 590590 569569 500500 460460 400400

ResultsResults

With all the facts gathered from the With all the facts gathered from the experiment the conclusion made was that experiment the conclusion made was that the spec-20 D is used to calculate the spec-20 D is used to calculate absorbance, transmittance, and absorbance, transmittance, and concentration of a certain wavelength. In concentration of a certain wavelength. In the experiment it was able to be the experiment it was able to be determined that certain colors were determined that certain colors were produced with certain wavelength. It was produced with certain wavelength. It was able to be known the function of each part able to be known the function of each part of the machine. The lab could’ve went of the machine. The lab could’ve went wrong if the controls were not working or if wrong if the controls were not working or if the students didn’t pay attention. the students didn’t pay attention. Improvements to lab are unknown.Improvements to lab are unknown.

SpecsSpecs

To determine the amount of To determine the amount of aspirin in a commercial aspirin aspirin in a commercial aspirin product. This lab may also be product. This lab may also be used to determine the purity of used to determine the purity of the aspirin produced in the the aspirin produced in the Microscale Synthesis of Microscale Synthesis of Acetylsalicylic Acid lab.Acetylsalicylic Acid lab.

Data Chart for Absorbance Data Chart for Absorbance AverageAverage

Sample 2.5 2.0 1.5 1.0 0.5

salicylic acid0.3510 0.3163 0.2800 0.1797 0.1113

assured aspirin0.047 0.038333 0.04 0.024667 0.009667

enteric aspirin0.107333 0.201333 0.087333 0.074333 0.116

Chemistry IA 0.04 0.012667 0.029 -0.009333 -0.018

Chemistry IB -0.020333 -0.096667 0.096 -0.008 -0.022333

Chemistry II 0.001 -0.017333 -0.021333 -0.030333 -0.036333

acetylsalicylic acid0.078 0.068333 0.062333 0.082667 0.025667

acetic anhydride0.095333 0.087667 -30.68033 -0.028 -0.071667

acetic acid0.014667 -0.019333 0.005333 0.003 0.006

phosphoric acid0.461333 0.273333 0.182333 0.133333 0.108333

Data Chart for Data Chart for Transmittance AverageTransmittance Average

Sample 2.5 2.0 1.5 1.0 0.5

salicylic acid 44.6667 48.2667 52.8667 66.2000 77.4000

assured aspirin

84.13333 86.93333 86.93333 91.8 91.8

enteric aspirin 77.93333 63.86667 55.7 84.26667 77.73333

Chemistry IA 91 97.33333 93.6 102.1333 104.4667

Chemistry IB 111.1333 110.5333 80.4 101.6667 105.5

Chemistry II 100 105.1333 105.1333 107.2 108.6667

acetylsalicylic acid

83.6 85.4 86.6 94.93333 94.2

acetic anhydride

76.33333 81.2 104.9333 105.9333 116.1333

acetic acid 64.34033 71.13233 66.939 65.06333 66.33767

phosphoric acid

59.305 68.31467 67.124 66.78167 67.38133

Salicylic AcidSalicylic Acid

Absorbance and Concentration for Salicylic Acid

0.3510

0.3163

0.2800

0.1797

0.1113

0.0000

0.0500

0.1000

0.1500

0.2000

0.2500

0.3000

0.3500

0.4000

1 2 3 4 5

Concentration

Abso

rban

ce Series1

Transmittance and Concentraion for Salicylic Acid

44.6667

48.2667

52.8667

66.2000

77.4000

0.0000

10.0000

20.0000

30.0000

40.0000

50.0000

60.0000

70.0000

80.0000

90.0000

1 2 3 4 5

Concentration

Tran

smitt

ace

Series1

Assured AspirinAssured Aspirin

Absorbance and Concentration for Assured

0.047

0.0383333330.04

0.024666667

0.009666667

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

0.05

1 2 3 4 5

Concentration

Abso

rban

ce

Series1

Transmittance and Concentration for Assured

84.13333333

86.93333333 86.93333333

91.8

96.93333333

75

80

85

90

95

100

1 2 3 4 5

Concentration

Tran

smitt

ance Series1

Enteric AspirinEnteric Aspirin

Absorbance and Concentration for Enteric

0.107333333

0.201333333

0.087333333

0.074333333

0.116

0

0.05

0.1

0.15

0.2

0.25

1 2 3 4 5

Concentration

Abso

rban

ce

Series1

Transmittance and Concentration for Enteric

77.93333333

63.86666667

55.7

84.26666667

77.73333333

0

10

20

30

40

50

60

70

80

90

1 2 3 4 5

Concentration

Tran

smitt

ance Series1

Chemistry I AChemistry I A

Absorbance and Concentration for Chemistry 1 A

0.104

0.0596666670.055

0.15

0.125333333

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

1 2 3 4 5

Concentration

Abso

rban

ce Series1

Transmittance and Concentration for Chemistry 1 A

78.73333333

87.2 87.891.46666667

96.8

0

20

40

60

80

100

120

1 2 3 4 5

Concentration

Tran

smitt

ance

Series1

Chemistry I BChemistry I B

Absorbance and Concentration for Chemistry I B

-0.020333333

-0.096666667

0.096

-0.008

-0.022333333

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

1 2 3 4 5

Concentration

Series1

Transmittance and Concentration for Chemistry I B

111.1333333 110.5333333

80.4

101.6666667105.5

0

20

40

60

80

100

120

1 2 3 4 5

Concentration

Series1

Chemistry IIChemistry II

Absorbance and Concentration for Chemistry II

0.001

-0.017333333

-0.021333333

-0.030333333

-0.036333333

-0.04

-0.035

-0.03

-0.025

-0.02

-0.015

-0.01

-0.005

0

0.005

1 2 3 4 5

Concentr ation

Series1

Transmittance and Concentration for Chemistry II

100

105.1333333 105.1333333

107.2

108.6666667

94

96

98

100

102

104

106

108

110

1 2 3 4 5

Concentration

Series1

Acetylsalylic AcidAcetylsalylic Acid

Absorbance and Concentration for Acetylsalicylic Acid

0.078

0.068333333

0.062333333

0.082666667

0.025666667

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

1 2 3 4 5

Concentration

Abso

rban

ce

Series1

Transmittance and Concentration for Acetylsalicylic Acid

83.6

85.4

86.6

94.9333333394.2

76

78

80

82

84

86

88

90

92

94

96

1 2 3 4 5

Concentration

Tran

smitt

ance Series1

Acetic AnhydrideAcetic Anhydride

Absorbance and Concentration for Acetic Anhydride

0.095333333 0.087666667

-30.68033333

-0.028 -0.071666667

-35

-30

-25

-20

-15

-10

-5

0

5

1 2 3 4 5

Concentration

Series1

Transmittance and Concentration for Acetic Anhydride

76.3333333381.2

104.9333333 105.9333333

116.1333333

0

20

40

60

80

100

120

140

1 2 3 4 5

Concentration

Series1

Acetic AcidAcetic Acid

Absorbance and Concentration for Acetic Acid

0.014666667

-0.019333333

0.005333333

0.003

0.006

-0.025

-0.02

-0.015

-0.01

-0.005

0

0.005

0.01

0.015

0.02

1 2 3 4 5

Concentration

Series1

Transmittance and Concentration for Acetic Acid

64.34033333

71.13233333

66.939

65.06333333

66.33766667

60

62

64

66

68

70

72

1 2 3 4 5

Concentration

Series1

Phosphoric AcidPhosphoric Acid

Absorbance and Concentration for Phosperic Acid

0.461333333

0.273333333

0.182333333

0.133333333

0.108333333

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

1 2 3 4 5

Concentration

Abso

rban

ce Series1

Transmittance and Concentration for Phosphoric Acid

34.4

53.86666667

65.73333333

73.53333333

77.86666667

0

10

20

30

40

50

60

70

80

90

1 2 3 4 5

Concentration

Tran

smitt

ance

Series1

Absorbance ChartAbsorbance Chart

Absorbance Values

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Concentration

Concentration

Ab

so

rban

ce

standard

SA

Assured

Enteric

Acetylsalicylic Acid

Phosphoric Acid

Chem. IA

Chem. IB

Acetic Acid

Chem.2

Transmittance ValuesTransmittance Values

Transmittance Values

0

20

40

60

80

100

120

140

Concentration

Concentration

Tra

nsm

itta

nce

Standard

SA

Assured

Enteric

Acetylsalicylic Acid

Phosphpric

Chem. I A

Acetic Acid

Acetic Anhydride

Chem II

Chem I B

Results Results

In conclusion, none of the samples reached the absorbance standard. They all crossed each other but none reached the standard point. In transmittance, salicylic acid, acetic acid, phosphoric acid, and enteric acid all crossed the standard during the 0.5 line. The samples were not pure.

Conclusion

• The overall conclusion to the study found was the Chemistry II sample aspirin was not pure. The chemicals used to make the samples were not pure either. The Chemistry IA and Chemistry IB sample aspirin was not pure either. The chemicals used in the making the aspirin were originally pure but mixed together they came out in an impure form. The standardization of a pipette was a cause for an impure result. If the students were more precise with the count then when used in the making of acetylsalicylic acid the impurity would not have been thrown off. Relative purity showed the impure state. Reasons the relative purity possibly showed an impure result would be because the students put too much sample in the capillary tube to be tested so since the students were going off results written down instead of the first results from when the samples were made it would most likely have been pure. Melting points showed the chemicals used in the making of the aspirin were impure. Since the melting points of the chemicals of the chemical samples were not closely related to the standard they were impure because of contamination. The spec lab was the most obvious when it came to showing the impurity of the sample. The results showed in charts 2and 3 were nowhere near the standard.

•  

References

http://www2.volstate.edu/CHEM/1110/Labs/Spectrophotomery.htm

http://inventors.about.com/library/blaspirin.htm

http://www.ic.sunysb.edu/class/chel34/lectures/134pll.pdf

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Darryl Rodgers and Carlos McCants