Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Lab 6 chem 162 university of washington, Lab Reports of Chemistry

Lab 6 chem 162 university of washington

Typology: Lab Reports

2023/2024

Uploaded on 06/08/2025

kunchen-liang
kunchen-liang 🇺🇸

1 document

1 / 5

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
CHEM
162
LAB
#6:
SYNTHESIS
OF
ASPIRIN
Goals
of
this
lab:
Synthesize
aspirin
and
evaluate
the
product
for
purity
and
yield
Perform
stoichiometry
calculations
to
determine
expected
yield
vs.
percent
yield
Apply
Beer's
law
to
determine
the
amount
of
impurity
in
the
crude
product
Compare
melting
points
of
the
crude
product
and
pure
aspirin
to
evaluate
determine
relative
purity
of
the
product
Your
lab
report
will
be
grade
on
the
following
criteria
using
a
poor/good/excellent
rating
system:
Calculations
are
accurate
and
complete
based
on
data
gathered;
proper
significant
figures
and
units
are
used
Data
collected
is
reasonable;
measurements
are
careful
and
accurate
Conclusions
are
reasonable
and
logical
Lab
report
is
completed
neatly
with
organized
responses
and
legible
handwriting
By
signing
below,
you
certify
that
you
have
not
falsified
data,
that
you
have
not
plagiarized
any
part
of
this
lab
report,
and
that
all
calculations
and
responses
other
than
the
reporting
of
raw
data
are
your
own
independent
work.
Failure
to
sign
this
declaration
will
result
in
5
points
being
deducted
from
your
lab
score.
This
lab
is
worth
60
points:
10
points
for
notebook
pages,
50
points
for
the
lab
report
(Do
NOT
include
your
notebook
pages
when
you
scan
your
report
for
upload
into
Gradescope.)
Scanned
with
CamScanner
pf3
pf4
pf5

Partial preview of the text

Download Lab 6 chem 162 university of washington and more Lab Reports Chemistry in PDF only on Docsity!

CHEM 162 LAB #6: SYNTHESIS OF ASPIRIN

Goals of this lab:

  • Synthesize aspirin and evaluate the product for purity and yield
  • Perform stoichiometry calculations to determine expected yield vs. percent yield
  • • ApplyCompare Beer's melting law to points determine of the thecrude amount product of impurityand pure inaspirin the crude to evaluate product determine relative purity of the product Your • labCalculations report will beare grade accurate on the and following complete criteria based usingon data a poor/good/excellent gathered; proper significant rating system: figures and units are used
  • Data collected is reasonable; measurements are careful and accurate
  • Conclusions are reasonable and logical
  • Lab report is completed neatly with organized responses and legible handwriting

By part signing of this below, lab report, you certifyand that that all you calculations have not andfalsified responses data, thatother you than have the not reporting plagiarized of raw any data are your own independent work. Failure to sign this declaration will result in 5 points being deducted from your lab score.

This lab is worth 60 points: 10 points for notebook pages, 50 points for the lab report (Do NOT include your notebook pages when you scan your report for upload into Gradescope.)

NEATLY show your work. Use a reasonable number of significant figures, include units with your data, and keep your answers concise.

Part I. Synthesis of Aspirin

Table 1

Value Units Mass of salicylic acid (^) 0.210 9

Volume of acetic anhydride 0,48 mL

Volume of phosphoric acid (^2) drops

Temperature of reaction 6g.0 •c

Mass of filter paper + watch glass 31.6552 9

Mass product of filter paper+ watch glass + crude 21.920 9 ___

Part 1. I Calculations Calculate the actual and Results yield of crude aspirin product. Neatly show your work.

wield de Crude ospir n {Mass of filHterpapertqlosstproducf)-.

J K (woss 0f -finer poren*gass)

- 31 • “ 2 o 9 - 31 65 9 = 0.268q0spinn

Calculation summary: How much crude aspirin did you produce? 0.2^^

  1. The that procedurethis is the caserequires with that your acetic reaction anhydride by providing reactant a stoichiometry be present in calculationexcess. Demonstrate using your data the required and the densitywork and of explicitly acetic anhydride compare (1.082 the amounts g/mL). (^) ofFor reagents full credit, used. be sure to show all of

C7H(034 Ch ,3- C2HO2 —> I'-1 ratio

-5- Al 0~ 3 mls \

। dee 11 c jdr i de

  • 0.21^ Oq^ Sovicle\38.1219^ o(d^ (^ ___ (52x1d JOliCu^ mols lie i \vnol^ **^ mol peetcCol. acid^ eo.

1 .51x10“ 3 ryols sal i

3 1-2x/0Kmols-imHaAAaerycuapt no. j m excess

Page 2 of 5

NA (^) Quiz Section

Part II Calculations and Results

  1. In the following table, copy the required values from Part II Table 2: _________ .913___________________________^ .0Z)G Calculate the % salicylic acid in your product. For full credit, be sure to neatly show all of the

Absorbance Mass of crude product analyzed required work. A=EAc-c=A, — -+

201 X10-3yol/

Q5DM-^ ,1,013‘cpm• Ic 138, 1Mo

278X 0.02) a Calculation summary. What is the % impurity in your product?

  1. In the following table, copy the required MASS values from pages 2 and 3:

Calculation summary: What is the corrected % yield for your synthesis reaction? 112. % glelo

  1. What factors contribute to the % yield being high/low? The experime rtaN yield fovihe Salicylic Ocd isstqn/lu Dighc ihan the heorenical yield - This WOS hivel - dv t -ve sompl for por-1 T no bemo (ompletelu dqted 00+.Ths woold c^e the VoSS - loxqer -han i1 OCNOl9 WQS- Page 4 of 5

Part III. Melting Point Determination

Table 3.

Quiz Section CD

Part III Results and Discussion

  1. Compare sample. How and wouldcontrast you the expect melting the points data for observed your product for your to samplediffer from and thethe purepure compound?aspirin Does your data follow that prediction/expectation?

Range Units Trial #1 for crude aspirin sample (^) 152.1-15.9 ‘ 0 Trial #2 for crude aspirin sample (^) 153.7-/57.3 °C Pure aspirin sample (^) 136.2-13q.2 °C

The wo MOlS wirth the erode OSpri) hve lovger pomiS than -rhe pore aspirin Somple.T/SIS -the vSvH we expeded. n+e crde ospirn l(kelo (onounino POrihes, the vettho pomt WOs (ower. - Ths IS cavsdouthewpovHles disroptngtM€ inter- mble(vloy corce5 Movivo tt eosier dv brcl the bonds ond me(+ He crude spii CDMWpoved To-te pore ospiHH.

Page 5 of 5