EVALUATION OF A COLLECTION AND '
ANALYTICAL PROCEDURE FOR VINYL CHLORIDE
IN AIR
FOR
U.S. ENVIRONMENTAL PROTECTION AGENCY
CONTRACT NO. 68-02-1408
TASK ORDER NO. 2
EPA Report No. 75-VCL-l
"The contents of this report do not necessarily
reflect the views and policies of the Environ-
mental Protection Agency, nor does mention of
trade names or commercial products constitute
endorsement or recommendation for use."
December 13, 1974
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INTRODUCTION
The purpose of Task Order No. 2 was to evaluate the
feasibility of source testing for vinyl chloride (VC)
using a gaseous grab sampling method with Tedlar bags
followed by gas chromatographic analysis. According
to this task order, gas-tight syringes were to be used
for all sample injections. The completion of this task
should provide sufficient data on the reproducibility
of the analytical method for 5, 50, 500, and 1000 ppra
(v/v) of vinyl chloride in air, the possible inter-
ference of a number of specified organic compounds,
and the stability of gaseous vinyl chloride samples
under a prescribed set of conditions.
EXPERIMENTAL
In executing Step 1 of the Task Order (see Appendix IV),
a series of 5-, 50-, 500-, and 1000-ppm gas mixtures
of vinyl chloride in air was prepared five times on
four separate days using a static dilution procedure.
In addition, the 5-ppm vinyl chloride gas mixture was
prepared an additional six times each, using a static
and a dynamic dilution system. The analysis of each
gas mixture was performed in triplicate by gas chroma-
tography.
In performing Step 2, the potentially interfering sub-
stances were added in sequence to a 500-ppm gaseous mix-
ture of vinyl chloride in air. Two, 5-ml portions of
the mixture were analyzed after preparation of the vinyl
chloride-air mixture as well as after each of the sequen-
tial 500-ppm additions of the 11 potential interferences
which consisted of the following compounds listed in the
order of their respective additions: methane, ethane,
ethylene, ethyl chloride, n-pentane, 1,1-dichloroethane
(ethylidene chloride), vinyl acetate, n-hexane, 1,1-di-
chloroethylene (vinylidene chloride), 1,1,1-trichloro-
ethane and n-heptane. After the sequential addition and
analysis of these mixtures, water vapor was added to
yield approximately a 10 percent (v/v) water vapor con-
centration in the mixture which was then analyzed in
duplicate. Hydrogen chloride was then added to yield
a 50-ppm concentration and the final set of duplicate
analyses for VC was performed.
Step 3 of the Task Order required the determination of
the possible degradation of 5 and 500 ppm vinyl chloride-
gas mixtures in either of two sets of Tedlar air bags
which contained several of the possible interferences
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-2-
investigated in Step 2; one set was maintained at room
temperature, the other at the dewpoint of a 10% water
vapor mixture. The two sets of Tedlar air bag gaseous
mixtures were prepared by similar procedures and, in
addition to 5 and 500 ppm of vinyl chloride contained
500 ppm of each of the following: methane, ethane,
ethylene, ethyl chloride, n-pentane, and vinyl chloride,
10 percent water vapor, and 50 ppm of hydrogen chloride.
Duplicate analyses were performed on each gas-vapor
mixture immediately upon generation and again after 6,
24, and 48 hours.
RESULTS
Reproducibility of the Gas Chromatographic Method
The gas mixtures consisting of 5, 50, 500 and 1000 ppm
of vinyl chloride (VC) in air contained in Tedlar bags
were analyzed by gas chromatography. on Chromosorb 102
using flame ionization detection. The gas mixtures
were prepared statically in 19-liter Tedlar bags pro-
vided with Nylon fittings, the opening of which was
sealed with a rubber serum cap. A 5-ml gas-tight
syringe was used to withdraw a portion of the gas mix-
ture for analysis. The results of this study are
summarized in Tables I-IV.
As shown in Tables I-IV there was a marked variation
in the vinyl chloride equivalent peak areas for the
four VC gas mixtures from one trial to the next. How-
ever, the mean deviation of repeated analyses of any
one trial was within three percent in 17 of the 20
trials.
The observed variations from one trial to another, con-
ducted on different dates, demonstrate the need for
repetitive re-standardization of the method with each
group of unknown samples. The data shown presented in
Tables V and VI are the results of the analysis of 5-
ppm VC standards prepared statically with a 50-ml gas-
tight syringe (Table V) and dynamically (Table VI).
Table V demonstrates that the use of a single 50-ml gas-
tight syringe is an improvement over five 10-ml portions.
The dynamic preparation of a 5 ppm vinyl chloride standard
from a 100 ppm standard produced a sample whose average
equivalent areas more closely approximated those obtained
for the higher concentrations. However, the mean devia-
tion per trial showed no improvement for this method over
the static method of sample preparation. None of the
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-3-
compounds investigated had a retention time on the
Chroraosorb 102 column sufficiently close to that of
vinyl chloride to constitute a serious qualitative
interference.
Table VIII present the measured vinyl chloride peak
areas in the presence of the listed interferences,
along with the equivalent areas, expressed in terms
of mm^/ppm, adjusted to correct for overnight changes
in the sensitivity of the gas chromatographic method
(sensitivity changes were observed in Step 1 during
the evaluation of the reproducibility of the method).
Degradation of Vinyl Chloride - Gas Mixtures
The deterioration of air mixtures containing vinyl
chloride and potential interferences was investigated.
Gas-air mixtures containing 5 and 500 ppm each of
vinyl chloride plus added potential interferences were
analyzed at 0, 6, 24 and 48 hours. Duplicate prepara-
tions of the gas mixtures were made; one set being
maintained at ambient temperature, the other at the
dew point of a 10% water vapor mixture. The results
cf this study, tabulated in Tables IX and X, give no
evidence of degradation of vinyl chloride during the
48-hour residence period in the Tedlar bags.
COMMENTS
j
The gas chromatograph was allowed to remain completely
operational day and night to minimize variable detector
response characteristics. In addition, the gas chroma-
tograph was recalibrated daily with a 500 ppm VC-air
mixture prepared as described above for Step 1. This
calibration was proved to be reproducible in Step 1.
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SAMPLING AND ANALYTICAL EQUIPMENT PROCEDURES
Equipment
1. Pye Unicam Series 104 Gas Chromatograph with Flame
lonization Detector.
I
2. 80/100 mesh Chromosorb 102 Gas Chromatographic Column
(2.4 meters ~x. 0.64 cm~)~- " ' ^
3. Philips Model PM8000 Strip Chart Recorder.
i
4. Hamilton Gas-Tight Syringes, 1-ml, 5-ml, 10-ml and
50-ml.
5. Hamilton Syringe, 50-yl, Model No. 705N.
6. 19-liter Tedlar Bags, Model No. 1234, Plastic Film
Enterprises.
7. Mark III Flowmeter, Fisher Scientific Company.
8. Flowmeter, Type 1211-1355-8506, Brooks Instrument
Division.
Procedures
Step 1
The 50-ppm vinyl chloride gas mixture was prepared by
injecting, with a 1-ml gas-tight syringe, 0.5 ml of pure
vinyl chloride gas into an 19-liter Tedlar bag while the
latter was being charged with 10 liters of air. The air
was purified by passage through 20/50 mesh activated coco-
nut charcoal at a rate of 1.0 liter per minute; the air
flow was monitored with a calibrated gas flowmeter. The
pure vinyl chloride had previously been transferred from a
Matheson lecture bottle into a 250-ml evacuated Saran bag,
from which it was withdrawn using the gas-tight syringes
for the preparation of the desired concentrations. After
preparing each mixture, the inlet tubing was removed and
the bag sealed with a rubber serum cap. The 500- and 1000-
ppm mixtures were prepared in a similar manner using 5 and
10 ml of vinyl chloride gas, respectively.
The 5-ppm gas mixture was prepared according to the
following procedure. While the 19-liter Tedlar bag was
being charged with 10 liters of purified air, five 10-ml
portions of a previously prepared 1000 ppm vinyl chloride
gas mixture were injected into the air line. This method
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of 5 ppm vinyl chloride preparation did not yield con-
sistent results and two other methods were investigated.
1) A single 50-ral injection was employed to reduce the
number of injections of the 1000 ppra solution from five
to one. The results of the subsequent analyses differed
only slightly from the previous"" 5 ppm gas standard. 2)
The dynamic dilution of a commercially prepared 100 ppm
vinyl chloride gas mixture (Liquid Carbonic). The
following schematic diagram depicts the apparatus used
to dynamically generate the 5 ppm VC Standard.
compressed
air
19-liter Tedlar Bag
100 ppm VC in
The flowrate of the compressed air was nineteen times
as great as the flowrate of the 100 ppm vinyl chloride
gas standard. The results of the subsequent analyses
are tabulated in Tables V and VI.
Each gas mixture was mixed thoroughly. Analysis in
triplicate was accomplished by the injection of 5 ml of
the mixture onto the gas chromatographic column with a
5-ml gas-tight syringe. The conditions for the gas
chromatograph throughout Step 1 were as follows: oven
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temperature, 155°C; detector temperature, 225°C; helium
carrier flowrate, 40 ml/tnin.; 2.4 meter x 0.64 cm
Chromosorb 102 column.
Step 2
A group of 11 organic compounds, water vapor and hydro-
gen chloride was evaluated to determine their additive
and possible qualitative or quantitative interference on
the analysis of vinyl chloride. Due to the problems in
reproducing a 5-ppm vinyl chloride mixture, this part
was completed only on the 500-ppm gas mixture. A 500-
ppm vinyl chloride gas mixture, was prepared, as described
in Step 1, and analyzed in duplicate by injecting 5 ml
of the mixture on the Chromosorb 102 column using a 5-ml
gas-tight syringe. Five ml of methane was then intro-
duced into the Tedlar bag by means of a gas-tight syringe
to yield a resulting gas mixture containing 500 ppm of
vinyl chloride and 500 ppm of methane. Again, duplicate
analyses were performed. The remaining potential inter-
ferences were added sequentially with duplicate analysis
following each addition. The following organic compounds
were investigated for their potential interference in the
vinyl chloride analysis: methane, ethane, ethylene,
ethyl chloride, n-pentane, 1,1-dichloroethane (ethylidene
chloride) vinyl acetate, n-hexane, 1,1-dichloroethylene
(vinylidene chloride), 1,1,1-trichloroethane, and n-heptane.
Methane, ethane, ethylene, and ethyl chloride are gases-
at room teperature and atmospheric pressure and were
added to the vinyl chloride gas mixture with a gas-tight
syringe, The remaining compounds are liquids at room
temperature and atmospheric pressure and were therefore
introduced into the gas mixture by means of a 50-pl
Hamilton liquid syringe (Model No. 705N). In each case,
calculations were performed to determine the amount of
each liquid required to yield a 500-ppm concentration in
10 liters of gas. Following the addition of the last
contaminant, i.e., n-heptane, water vapor was added from
a steam generator to produce a 10 percent (v/v) concen-
tration of water vapor in the Tedlar bag. The water vapor
was allowed to condense on the walls of the bag (at room
temperature) and duplicate analyses for vinyl chloride
were performed. Hydrogen chloride gas (0.5 ml) was then
added to the gas mixture. This produced a concentration
of 50 ppm of HC1 vapor. Duplicate analyses for vinyl
chloride were again performed.
A fresh 500-ppm vinyl chloride solution was prepared
daily and analyzed. The interferences which had been
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added by the time of the conclusion of the previous
day's work were then added and the investigatory
scheme was continued.
Step 3
This step was performed to evaluate the possible deter-
ioration of vinyl chloride in a Tedlar bag over a period
of 48 hours (see Appendix IV). Two sets of two identical
bags were charged with air containing 5 and 500 ppm,
respectively, of vinyl chloride and 500 ppm concentra-
tions of each of the following contaminants: methane,
ethane, ethylene, ethyl chloride and n-pentane. To each
gas-mixture water vapor and hydrogen chloride were added
as described in Step 2 (10% water vapor and 50 ppm HC1
vapor in the final mixtures). Those contaminants whose
retention times were greater than twenty minutes were
omitted from Step 3 to accelerate the completion of the
analyses.
Each mixture was analyzed in duplicate following injection
of 5 ml onto the gas chromatographic column. One 5-ppm
gas mixture and one 500-ppm gas mixture were stored in a
forced-draft oven (Blue M) at 115°F, the water vapor dew-
point of 10 percent water vapor in air (Perry' s Chemical
Engineer's Handbook, Perry, J.H., (ed.), McGraw-Hill,
New York, 1963, p. 15-5). The other two mixtures were
maintained at room temperature, which varied from 71-76°F
over the 48-hour period. Each gas mixture was subsequently
analyzed, in duplicate, after 6, 24, and 48 hours of resi-
dence in a Tedlar bag.
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APPENDIX I
TABLES
I. Reproducibility of the Gas Chromatographic Analysis of
5-ppm VC Mixtures in Air
II. Reproducibility of the Gas Chromatographic Analysis of
50-ppm VC Mixtures in Air
III. Reproducibility of the Gas Chromatographic Analysis of
500-ppm VC Mixtures in Air
IV. Reproducibility of the Gas Chromatographic Analysis of
1000-ppm VC Gas Mixtures in Air
V. Reproducibility of the Gas Chromatographic Analysis of
5-ppm Vinyl Chloride Standards Prepared with a 50-ml
Gas-Tight Syringe
VI. Reproducibility of the Gas Chromatographic Analysis of
5-ppm Vinyl Chloride Gas Standards Prepared by the
Dynamic Dilution of a 100-ppm Vinyl Chloride Standard
VII. Potential Interferences Investigated and Their Absolute
and Relative Retention Times
VIII. Vinyl Chloride Peak Areas in the Presence of Potential
Interferences
IX. Degradation of 5 ppm Vinyl Chloride in Gas Mixtures
Containing Potential Interferences Stored for Stated
Periods
X. Degradation of 500 ppm Vinyl Chloride in Gas Mixtures
Containing Potential Interferences Stored for Stated
Periods
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TABLE I
REPRODUCIBILITY OF THE GAS CHROMATOGRAPHIC ANALYSIS
OF 5-PPM VC MIXTURES IN AIR
Equivalent Area*
Mean Deviation Per Trial
Itidl Separate Analyses
No. (n,m2/?pm)
1 9284
8704
7752
2 5760
5120
4880
3 3460
3400
3400
'4 6436
6356
6124
5 7812
8112
7752
*F.atiivalent Area =
Average
(mm /ppm)
8580
5253
3420
6305
7892
Peak Area
2
(mm /ppm) %
552 6.4
338 6.4
27 0.8
121 1.9
147 1.9
x Attenuation
PPM of Vinyl Chloride in Air
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TABLE II
REPRODUCIBILITY OF THE GAS CHROMATOGRAPHIC ANALYSIS
OF 50-PPM VC MIXTURES IN AIR
Equivalent Area*
Mean Deviation Per Trial
iriai
No.
1
2
3
4
5
Separate Analyses
(mm /ppm)
7032
7256
" 7108
6396
6552
5680
5760
5880
5760
9440
9284
9424
10804
10716
10716
Average
(mm^/ppm) (mm /ppm) %
7132 83 1.2
5781 496 8.6
5800 53 0.9
9383 66 0.7
10745 39 0.4
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TABLE III
REPRODUCIBILITY OF THE GAS CHROMATOGRAPHIC ANALYSIS
OF 500-PPM VC MIXTURES IN AIR
Mean Deviation Per Trial
Trial
No.
1
.
2
3
4
5
Separate Analyses
(mm /ppm)
^ ****** * r r '
7372
7412
6450
6145
6095
6280
6080
6240
9120
9196
9120
10180
10300
10184
Average
(mm /ppm)
7392
6209
6200
9145
10221
2
(mm / p pra )
20
140
80
34
52
0.3
2.3
1.3
0.4
,
0.5
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TABLE IV
REPRODUCIBILITY OF THE GAS CHROMATOGRAPHIC ANALYSIS
OF 1000-PPM VC GAS MIXTURES IN AIR
Mean Deviation Per Trial
mai
No.
1
2
3
'4
5
Separate Analyses
'(mm /ppm)
7270
7125 .
7220
6450
6145
6095
6220
6320
6240
8626
8970
8932
10120
10120
10165
Average
(mm /ppm)
7205
6230
6260
8843
10135
2
(mm /ppm) %
53 0.7
147 2.4
40 0.6
«-
144 1.6
20 0.2
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TABLE V
REPRODUCIBILITY OF THE GAS QHROMATOGRAPHIC ANALYSIS
OF 5-PPM VINYL CHLORIDE STANDARDS
PREPARED WITH A 50-ML GAS-TIGHT SYRINGE
Equivalent Area* Mean Deviation Per Trial
rp * * _^_^__^__.^__________^_.^____^__
i. LI. ai. Separate Analyses Average _
"°* (mm^/ppm) (mm^/ppm) (mm /ppm) %
7260 7284 2'4 0.3
7308
7216 7158 58 0.8
7100
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TABLE VI
REPRODUCIBILITY OF THE GAS CHROMATOGRAPHIC ANALYSIS
OF 5-PPM VINYL CHLORIDE GAS STANDARDS
PREPARED BY THE DYNAMIC DILUTION OF
A 100-PPM VINYL CHLORIDE STANDARD
Mean Deviation Per Trial
Trial Separate Analyses Average
No' (mm2/ppm) (mm2/ppm)
1
.
2
3
4
12936
12672
12672
12912
11772
13164
13420
11220
12804
12792
12468
12320
2
(mm /ppra) %
132 1.0
120 0.9
696 5.6
.1100 8.9
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TABLE VII
POTENTIAL INTERFERENCES INVESTIGATED
AND THEIR ABSOLUTE AND RELATIVE RETENTION TIMES
(Relative to Vinyl Chloride Retention Time = 4.90 minutes)
Name
Methane
Ethylene
Ethane
Ethyl Chloride
1,1-Dichloro-
ethylene
(Vinylidene
Chloride)
n-Pentane
1,1-Dichloro-
ethane
(ethylidene
chloride)
Vinyl Acetate
n-Hexane
1,1,1-Trichloro-
ethane
n-Heptane
Formula
CH,
CH3-CH3
CH2«CHOC-CH3
Retention Time
(min. )
1.0
1.6
1.9
9.1
14.8
16.7
23.6
23.9
37.0
43.5
87.0
Relative .
Retention Time
0.20
0.33
0.39
1.9
3.0
3.4
4.8
4.9
7.6
8.9
18
'Retention Time was measured from time of injection.
Relative Retention Time=
Retention Time for Compound
Retention Time for Vinyl Chloride
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TABLE VIII
VINYL CHLORIDE PEAK AREAS IN THE PRESENCE OF POTENTIAL INTERFERENCES
Peak Area
Avg. Dev. from
Mixture Description
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(a')
(h)
(i)
(J)
(a")
(k)
(D
(a'")
(m)
(n)
500
(a)
(b)
(c)
(d)
(e)
(f)
500
(8)
(h)
(i)
500
(J)
(k)
500
(D
(m)
ppm VC
+ 500
+ 500
+ 500
+ 500
+ 500
+ 500
ppm
ppm
ppm
ppm
ppm
ppm
methane
ethane
ethylene
methyl chloride
n-pentane
1, 1-dichloroethane
ppm VC
+ 500
+ 500
+ 500
ppm
ppm
ppm
vinyl acetate
hexane
vinylidene chloride
ppm VC
+ 500
+ 500
ppm
ppm
1,1,1-trichloro ethane
n-heptane
ppm VC
+ 10%
+ 50
water vapor
ppm
HC1
Date
8/27/74
8/27/74
8/27/74
8/27/74
8/27/74
8/27/74
8/27/74
8/28/74
8/28/74
8/28/74
8/23/74
8/29/74
8/29/74
8/29/74
8/30/74
8/30/74
8/30/74
Range
3201-3312
3648-3700
3293-3441
3150-3719
3293-3690
3528-3756
3626-3682
3120-3141
2916-2934
2826-2952
2983-2993
2945-2951
3003-3077
2912-2937
2907-3173
2024-3034
3024-3028
Avg .
3257
3674
3367
3435
3492
3642
3654
3131
2925
2889
2988
2948
3040
2925
3040
3029
3026
a, a', a",
+417
+110
+178
+235
+385
+397
-
-206
-242
-143
-
+92
-23
-
-11
-14
(12
(3.
(5.
(7.
(11
(12
(6.
(7.
(4.
(3.
(0.
(0.
(0.
or a'"
.8%)
3Z)
5%)
2%)
.8%)
.2%)
6%)
7%)
8%)
1%)
7%) ,
4Z)
5%)
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Begun 9/3 TABLE IX
DEGRADATION OF 5 PPM VINYL CHLORIDE IN GAS MIXTURES
CONTAINING POTENTIAL INTERFERENCES STORED FOR STATED PERIODS
Vinyl Chloride Peak Area (x 1/20)
Time
(hours)
0
6
24
48
100 PPM
VC
Standard*
1906
1887
(1.0%)
1848
(-3.0%)
2147
(+12.6%)
Room Temperature
Separate Analyses
(mm2)
2358
2358
2390
2380
2174
2376
2793
2910
Average
(mm2)
2358
2385
2275
2852
Deviation**
(mm2)
+27
(+1.1%)
-83
(-3.5%)
+494
(+20.9%)
Dew Point Terni
Separate Analyses
(mm 2)
2376
2327
2370
2399
2301
2299
2641
2793
serature (115°F)
Average
(mm 2)
2352
2385
2300
2717
Deviation**
(mm2)
+33
(+1.4%)
-52
(-2.2%)
+ 365
(+15.5%)
* Reference standard, prepared fresh daily without potential interferences
** Deviation from average area at t «* 0 hours
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Begun 8/27 TABLE X
DEGRADATION OF 500 PPM VINYL CHLORIDE IN GAS MIXTURES
CONTAINING POTENTIAL INTERFERENCES STORED FOR STATED PERIODS
Time
(hours)
0
6
24
48
500 ppm
VC Std.*
3257
3131
(-3.9%)
2948
(-9.5%)
Vinyl Chloride Peak Area (x 1/2000)
Room Temperature
Separate
Analyses
(mm2)
2309
2603
2508
2525
2889
2905
2868
2868
Average
(mm2)
2456
2517
2897
2868
Dev.**
(t-0
(mm 2 )
+61
(+2.5%)
+441
(+18%)
+412
(+16.8%)
Dew Point Temperature
Separate
Analyses
(mm 2 )
2363
. 2633
2496
2496
2821
2840
2610
2679
Average
2498
2496
2830
2645
Dev .**
(t-t0)
(mm 2 )
-2
(-0.08%)
+ 332
(13.3%)
+ 147
(+5.9%)
* Reference standard, prepared fresh daily without potential
interferences
** Deviation from 0 hours
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APPENDIX II
CHROMATOGRAHS
1. 5 ppm Vinyl Chloride Standard - Step 1
2. 5 ppm Vinyl Chloride Standard - Step 1
3. 5 ppm Vinyl Chloride Standard - Step 1
4. 500 ppm Vinyl Chloride Standard - Step 1
5. 500 ppm Vinyl Chloride Standard - Step 1
6. 500 ppm Vinyl Chloride .Standard - Step 1
7. 500 ppm Vinyl Chloride Gas Mixture plus Potential
Interferences - Step 2
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I-1 I ,( ! '
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n
I
St<
m
o
to
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APPENDIX III
SAMPLE CALCULATIONS
1. Peak Area - by Triangulation
Area - base x height
2321 - 19.5 mm x 119 mm
The peak areas are relative numbers and, hence, the
factor of 1/2 in the formula for the area of a triangle
(A-l/2 (b x h)) was deleted.
Absolute Peak Area » Area (at attenuation X) x X
e.g. Area - 2321 (attenuation « 20) x 20
- 46420
- 4.64 x 104
2. Equivalent Area is the peak area at an attenuation of
1 divided by the vinyl chloride concentration expressed
in ppm.
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Equivalent Area » Peak Area x Attenuation
Concentration of Vinyl Chloride
» 2321mm2 x 20
5ppm
2
9284 mm /ppm
3. Corrected Equivalent Area -ire^f^f-gctively the correction
of the equivalent area for a change in the gas chromato-
graphic response characteristics.
i
Corrected Equivalent Area = Equivalent Area x
(Time t)
.VC equiv. area (500 ppm, time ° 0)
VC equiv. area (500 ppm, time = t)
4. Generation of desired air Tro-ac-entrations of contaminants
from liquids. The volume of a liquid, which when evaporated
in a 10-liter gaseous air mixture, required to yield a
resulting 500-ppm concentration is calculated as follows:
Volume (ml) - Desired final^conc. (in ppm) x Air Volujne x
(in liters)
x Mol.Wt. x
Molar Gas Volume . liwj""t-' A Density of Liquid
Example for pentane:
_ , 500 ppm , rt , .,. Mole
Volume . 1QPP x 10 liters x 22.4 liters
0.6262g/ml
0.026 ml
Required
^Compound Density Volume (yl)
1,1,1-trichloroethane 1.3492 22
1,1-dichloroethane 1.1757 19
n-pentane 0.6262 26
n-hexane 0.6594 29
n-heptane 0.6838 33
vinyl acetate 0.9317 29
vinylidene chloride 1.218 18
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-3-
Generation of Water Vapor - The steam generator employed
consumes water at the rate of 90 ml per hour. The time
required for this steam generator to generate one liter
of steam (10% v/v) can be calculated according to the
following equation:
Time to Generate =
1 liter
1 liter Steam
r 17i
Molar Volume
- 1 liter
22.4 I/mole mole
0.54 min.
32 seconds
Rate of H20
consumption
(ml/min)
g/ml 9.5 ml/min
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