Determination of Butyl Ester of Stearic Acid in Polystyrene L. R. KILEY, The Daw Chemical Co., Midland,
Determination of Acetylsalicylic Acid, Phenacetin, and Caffeine in Mixtures
CS-14
Mich. Slit
Component
W. H. WASHBURN and E. 0. KRUEGER, AbboH Laboratories, North Chicago, 111.
Conc.
! 1
Component
'
1.
I
Stearic acid: C22H4402 butyl ester 1
I 1 0-10
AO.05
5.7 l a d i . sh.1
1
0 . 1 6 0 50 0.057 3 . 5
No./
1
1.
Instrument: Perkin-Elmer Model 12, NaCl prism Sample Phase: Solution in carbon tetrachloride Cell Windows: NaCl Absorbance Measurement: Calculation:
Base-Line-X
Inverted MatrixGra p hica I L L
Relative AbsorbanceQ-Analyticof
%
mm
~
~-
:
10.26 1 0.520 21.06 10.103 0 . 5 5 Instrumenf: Perkin-Elmer Model 12C, NaCl Prism Sample Phase: Solution in CHCI,
5.7
Cell Windows: NaCl Absorbance Measuremenf:
15.000
'"The relative absorbance i s given as the slope of the Beer's law concentration curve used expressed in terms o f absorbance per 100% o f constituent. ~
Calculofion:
CS-15
HUDSON, Ethyl Corp., Baton Rouge, La.
Base-Line-
Inverted MafrixGraphical-
Relative Absorbances-Analytical ComponentfX
1. 2. 3.
~~
Determination of Diethylaluminum Hydride and Diethylaluminum Ethoxide in Triethyl Aluminum
Point-X Successive A p p r o x . - Y
Matrix:
9.27
9.00
10.26
0.300 0.055 0.013
0.099 0.152 0.005
0.050 0.026 0.030
Moterial Purity: Reference compounds 9 9 +% pure Comments: Theoretical concentration of mixture i s 21.06 mg./ml. Theoretical concentration of each component is: acetylsalicylic acid, 1 1-34 mg./ml.; phenacetin, 8.1 mg./ml.; caffeine, 1.63 mg./ml. For details, see: Washburn, W . H., and Krueger, E. O., J. Am. Pharm. Asroc. Sc;. Ed. 38, 623 ( 1 949).
Determination of 2-Bromopentane and 3-Bromopentane Mixtures
-I
1
tion
4 . 8 5 0.042
0.093
F. A. SCHESKE and W. H. WASHBURN, Abbott Laboratories, North Chicago, 111.
CS- 17
1
Component
No.) 1.
~
1
2.
1. 2.
Cancn. mdml length
or y B.1. Pis.
9 . 2 7 0.557 21.06 0.117 0 . 5 5
AcetylCgH~04 salicylic acid j
Point-
Material Purity: Reference compounds 9 9 +yo pure Comments: Samples o f pure polystyrene, free o f the butyl ester o f stearic acid, are run to determine 1. Standards o f polystyrene plus the butyl ester o f stearic acid are run with each set o f samples to establish the analytical curve.
aluminum ethoxide
X
9 . 0 0 0.443 21.06 0.096 0 . 5 5
Matrix:
1.
L.
Formula
ACcuracy
Successive Approx.-
ComponentlX
R.
1
Name
CS-16
2 * 220 0.000
0.000 0.408
Nome
1
Formula
2-Bromopentane
'
CsHliBr
1
Slit
i'
(mm)
I 60-100
Ah or AV
10.2
zt1
Adjacent shoulders
I
------I
3-BrOmOpentane
CsHllBr
0-40
f l
,
12.3 12.112.8
Concn. % v/v Length mm
0.235 0.049
10
0.267 0.048
10 0.3
0.3
Maferiol Purity: AIEt2H was 9 6 % pure and a correction was applied. Comments: Triethylaluminum cells are loaded in a dry box. After run, the triethylaluminum sample i s blown from the cell with nitrogen and the cell is washed with an alcohol-hydrochloric acid mixture. The alcoholic HCl solution used i s 1 0 % 1 2 N HCI in alcohol. This solution is saturated with NaCl prior to use. The 4 . 8 5 ~base line point refers to the absorbance a t this wave length plus a constant used as reference absorbance. AlEtnOEt AIEt?H
Io = A 4 . 8 5 ~ Io = A4.85~
+ 0.083 + 0.129
These data represent standard publication and submission is opeu to an one in accordance with regulations of ANALYTICAL CHEMISTRY.The Cob?&& Society is acting only as an aid to the Journal. To standardize procedures ANALYTICAL CHEUI~TR requests Y that material be sent in quintuplicate to t i e chairman of the review committee. Robert C. Wilkerson, Celanese Corp. of America, Post Office Box 8, Clarkwbod, Tex.
1. 2. Material Purity: Comments:
0.340 0.000
0.000 0.864
Reference compounds 98% pure [no correction applied).
VOL. 29, NO. 12, DECEMBER 1 9 5 7
1895