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Calibration of plastic laboratory ware
Talentu, Vol. 28, pp. 781 to 783. 1981 Printed in Great Britain. All rights reserved
Copyright
CALIBRATION
ANALYTICAL
DATA
OF PLASTIC
LABORATORY
MARY
R.
0
0039-9l40/8l/[email protected]/0 1981 Pergamon Press Ltd 1981
WARE
MAWIN
Department of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen, Scotland (Received
11 February 1981. Accepted
9
March
1981)
Summary-The importance of the calibration of standard laboratory ware is pointed out. Tables for use in calibration of polypropylene and polymethylpentene vessels are presented.
A discrepancy in the concentration of a solution prepared in a 50%ml plastic (polypropylene) standard flask led to the discovery that there was an error of - 1.7 ml in the volume of the Aask. The results of a subsequent examination of a further thirty plastic flasks-which showed over half to have volume errors outwith the tolerances for Class B glassware-onfirm the need for a reminder of the importance of calibration of standard laboratory ware, even when only moderate accuracy is required. Comparison of values for the coefficient of cubical thermal expansion, y, derived from literature values for the coefficient of linear expansion for polypropylene’ and polymethylpentene2 (1.8-3.0 x 10m4 and 3.5 x low4 deg-‘) with those for borosilicate and soda glass (1.0 x lo-’ and 2.7 x lo-’ deg-‘) made it evident that the Tables for Use in Calibration of Volumetric Glassware3 would not be applicable. A short table of correction factors for plastics with y = 2, 3, 4, 5 and 6 x 10v4 deg- ’ is given in the British Standard for graduated plastic measuring cylinders4 but no indication is given of likely values of y for particular materials, and extensive interpolation would be required in use. The glasssware tables3 are calculated from the equation c=
v,,-
w
l_il+v(-N@t-~W A-a
1 (1)
where C is the correction to be added to the apparent weight in air of the water contained (or delivered), W, to obtain the volume of the vessel at 20”, V,e; c is the density of air at 20” and 760 mmHg, 0.0011994 g/cm3 ; A is the density of the weights, 8.0 g/cm3 (for stainless steel), and pt is the density of water at the temperature t (in “C). Density values for water were calculated from the equation given by Tilton and Taylor,5 then divided by 1.000028 to convert from g/ml (pre-SI definition) to g/cm3. TAL. 28/l+~
Equation (1) was evaluated for values of y from 2.0 x 1o-4 to 5.5 x 10Y4 deg- ’ in steps of 0.1 x 10e4, for a nominal volume of 100 ml, and for temperatures from 5 to 40”, to give a calibration table for each value of y. A series of calibration weighings of lOO-ml polypropylene and polymethylpentene standard flasks was then made, by the procedure recommended for glass flasks6 in which the water used to fill the flasks ranged in temperature from 5 to 40”. The volume at 20” was then calculated from each of several calibration tables for y-values in the region of the literature values. An additional correction of 0.0004 ml/deg was made to compensate for the difference between the temperature of the water and the surrounding air.’ For each set of values (over the whole temperature range) obtained from a particular table, the standard deviation of the calculated volumes was evaluated in order to find which table should be chosen. For polypropylene, the optimum table was the one for y = 3..0 x 10m4 deggr, and for polymethylpentene, the one for y = 4.3 x 10e4 deg-‘. In both cases, the standard deviation obtained by use of the best table was approximately the same as the standard deviation for a series of calibrations made at 20.0”, at which temperature the size of the correction factor is independent of y. The optimum tables are presented here, in the hope that they may be useful to British readers. Others should use them with caution, since different brands of plastic ware may have differing thermal-expansion properties. If there is any doubt, it would be a useful precaution to work only at 20”. Both tables refer to vessels of nominal volume 100 ml: corrections for other volumes can be calculated by simple proportion. It is interesting to note that, although the actual volumes of plastic vessels change with temperature by a much greater amount than do the volumes of glass ones, the weights of water contained vary by rather less. This is illustrated in Table 3.
781
782
ANALYTICAL
DATA
Table 1. Calibration table for polypropylene [nominal capacity 100 ml; coefficient of thermal expansion 3.0 x lo-“ deg-‘; add to weight (g) of distilled water at the temperature of measurement, to obtain volume (ml) at 20”]
5 6 1 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.558 0.531 0.504 0.480 0.456 0.435 0.414 0.395 0.377 0.360 0.345 0.330 0.317 0.305 0.294 0.284 0.276 0.268 0.261 0.256 0.251 0.247 0.244 0.243 0.242 0.242 0.243 0.244 0.247 0.250 0.255 0.260 0.266 0.273 0.280 0.288
0.555 0.528 0.502 0.477 0.454 0.433 0.412 0.393 0.375 0.359 0.343 0.329 0.316 0.304 0.293 0.284 0.215 0.267 0.261 0.255 0.251 0.247 0.244 0.242 0.242 0.242 0.243 0.245 0.241 0.251 0.255 0.260 0.266 0.273 0.281 0.289
0.553 0.525 0.499 0.475 0.452 0.430 0.410 0.391 0.373 0.357 0.342 0.328 0.315 0.303 0.292 0.283 0.274 0.267 0.260 0.255 d.250 0.247 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.251 0.256 0.261 0.267 0.274 0.282 0.290
0.550 0.523 0.497 0.473 0.450 0.428 0.408 0.389 0.372 0.355 0.340 0.326 0.314 0.302 0.291 0.282 0.273 0.266 0.260 0.254 0.250 0.246 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.252 0.256 0.262 0.268 0.275 0.283 0.291
0.547 0.520 0.494 0.470 0.448 0.426 0.406 0.388 0.370 0.354 0.339 0.325 0.312 0.301 0.290 0.281 0.273 0.265 0.259 0.254 0.249 0.246 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.252 0.257 0.262 0.268 0.276 0.283 0.292
0.544 0.517 0.492 0.468 0.445 0.424 0.404 0.386 0.368 0.352 0.337 0.324 0.311 0.300 0.289 0.280 0.272 0.265 0.258 0.253 0.249 0.246 0.243 0.242 0.242 0.242 0.243 0.246 0.249 0.252 0.257 0.263 0.269 0.27;
0.541 0.515 0.489 0.466 0.443 0.422 0.402 0.384 0.367 0.351 0.336 0.322 0.310 0.299 0.288 0.279 0.271 0.264 0.258 0.253 0.249 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.249 0.253 0.258 0.263 0.270 0.271 0.285 0.294
0.539 0.512 0.481 0.463 0.441 0.420 0.400 0.382 0.365 0.349 0.335 0.321 0.309 0.297 0.287 0.278 0.270 0.263 0.257 0.252 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.249 0.253 0.258 0.264 0.270 0.278 0.286 0.295
0.536 0.510 0.485 0.461 0.439 0.418 0.399 0.380 0.363 0.348 0.333 0.320 0.308 0.296 0.286 0.277 0.269 0.263 0.257 0.252 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.250 0.254 0.259 0.265 0.271 0.279 0.287 0.296
0.533 0.507 0.482 0.459 0.437 0.416 0.397 0.379 0.362 0.346 0.332 0.318 0.306 0.295 0.285 0.277 0.269 0.262 0.256 0.251 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.247 0.250 0.254 0.259 0.265 0.272 0.279 0.288 0.297
0.2a4 0.293
ANALYTICAL
783
DATA
Table 2. Calibration table for polymethylpentene [nominal capacity 100 ml; coefficient of thermal expansion 4.3 x lo-’ deg-’ ; add to weight (g) of distilled water at the temperature of measurement, to obtain volume (ml) at 20”] Temp.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
0.753 0.712 0.673 0.636 0.599 0.564 0.531 0.499 0.468 0.438 0.410 0.382 0.356 0.331 0.307 0.284 0.263 0.242 0.222 0.204 0.186 0.170 0.154 0.139 0.125 0.112 0.100 0.089 0.079 0.070 0.061 0.053 0.047 0.040 0.035 0.031
0.749 0.708 0.669 0.632 0.596 0.561 0.528 0.496 0.465 0.435 0.407 0.380 0.354 0.329 0.305 0.282 0.261 0.240 0.221 0.202 0.185 0.168 0.152 0.138 0.124 0.111 0.099 0.088 0.078 0.069 0.060 0.053 0.046 0.040 0.035 0.030
0.745 0.704 0.666 0.628 0.592 0.558 0.524 0.492 0.462 0.432 0.404 0.377 0.351 0.326 0.303 0.280 0.259 0.238 0.219 0.200 0.183 0.166 0.151 0.136 0.123 0.110 0.098 0.087 0.077 0.068 0.059 0.052 0.045 0.039 0.034 0.030
0.741 0.700 0.662 0.625 0.589 0.554 0.521 0.489 0.459 0.429 0.401 0.374 0.349 0.324 0.300 0.278 0.256. 0.236 0.217 0.198 0.181 0.165 0.149 0.135 0.121 0.109 0.097 0.086 0.076 0.067 0.059 0.05 1 0.045 0.039 0.034 0.030
0.737 0.697 0.658 0.621 0.585 0.551 0.518 0.486 0.456 0.427 0.399 0.372 0.346 0.321 0.298 0.276 0.254 0.234 0.215 0.197 0.179 0.163 0.148 0.133 0.120 0.107 0.096 0.085 0.075 0.066 0.058 0.051 0.044 0.038 0.033 0.029
0.732 0.693 0.654 0.617 0.582 0.548 0.515 0.483 0.453 0.424 0.396 0.369 0.344 0.319 0.296 0.273 0.252 0.232 0.213 0.195 0.178 0.162 0.146 0.132 0.119 0.106 0.095 0.084 0.074 0.065 0.057 0.050 0.043 0.038 0.033 0.029
0.728 0.689 0.650 0.614 0.578 0.544 0.511 0.480 0.450 0.421 0.393 0.366 0.341 0.317 0.293 0.271 0.250 0.230 0.211 0.193 0.176 0.160 0.145 0.131 0.117 0.105 0.094 0.083 0.073 0.064 0.056 0.049 0.043 0.037 0.032 0.029
0.724 0.685 0.647 0.610 0.575 0.541 0.508 0.477 0.447 0.418 0.390 0.364 0.339 0.314 0.291 0.269 0.248 0.228 0.209 0.191 0.174 0.158 0.143 0.129 0.116 0.104 0.092 0.082 0.072 0.064 0.056 0.048 0.042 0.037 0.032 0.028
0.720 0.681 0.643 0.606 0.571 0.538 0.505 0.474 0.444 0.415 0.388 0.361 0.336 0.312 0.289 0.267 0.246 0.226 0.207 0.190 0.173 0.157 0.142 0.128 0.115 0.103 0.091 0.081 0.071 0.063 0.055 0.048 0.042 0.036 0.032 0.028
0.716 0.677 0.639 0.603 0.568 0.534 0.502 0.471 0.441 0.412 0.385 0.359 0.334 0.310 0.287 0.265 0.244 0.224 0.206 0.188 0.171 0.155 0.141 0.127 0.114 0.102 0.090 0.080 0.071 0.062 0.054 0.047 0.041 0.036 0.031
30 31 32 33 34 35 36 37 38 39 40
Table 3. Effect of temperature on lOO-ml vessels Borosilicate glass y=l.Ox 10-s Temperature “C 5 10 15 20 25 30 35 40
AV -0.015 -0.010 -0.005 0.0 0.005 0.010 0.015 0.020
W, 1.0016 1.0014 1.0008 1.0 0.9989 0.9975 0.9960 0.9942
Soda glass 7=2.7x 1O-5 AV -0.041 - 0.027 -0.014 0.0 0.014 0.027 0.041 0.054
W, 1.0014 1.0012 1.0098 1.0 0.9990 0.9977 0.9962 0.9945
Polypropylene y = 3.0 x 1o-4 AV -0.45 -0.30 -0.15 0.0 0.15 0.30 0.45 0.6
W, 0.9973 0.9985 0.9994 1.0 1.0003 1.0904 1.0003 l.tXlOO
Polymethylpentene y = 4.33 x 1o-4 AV -0.645 -0.43 -0.215 0.0 0.215 0.43 0.645 0.86
W, 0.9953 0.9972 0.9987 1.0 1.0001 1.0017 1.0023 1.0026
AV = difference in volume from 100.00 ml. W, = (weight of water contained)/(weigbt of water contained at 20”).
REFERENCES
1. G. W. C. Kaye and T. H. Laby, Tables of Physical and Chemical Constants, 14th Ed., p. 253. Longmans, London, 1973. 2. Encyclopedia of Polymer Science and Technology, Vol. 9, Interscience, New York, 1968.
3. B.S. 1797: 1968. 4. B.S. 5404: Part 2: 1977. 5. L. W. Tilton and J. K. Taylor, .I. Res. Nat!. Eur. Stds., 1937,18,205. 6. B.S. 1792: 1960. .7. I. M. Kolthoff and P. J. Elving, eds., Treatise on Analyrical Chemistry, Part 1, Vol. 7, p. 4312. Interscience, New York, 1967.
Copyright
CALIBRATION
ANALYTICAL
DATA
OF PLASTIC
LABORATORY
MARY
R.
0
0039-9l40/8l/[email protected]/0 1981 Pergamon Press Ltd 1981
WARE
MAWIN
Department of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen, Scotland (Received
11 February 1981. Accepted
9
March
1981)
Summary-The importance of the calibration of standard laboratory ware is pointed out. Tables for use in calibration of polypropylene and polymethylpentene vessels are presented.
A discrepancy in the concentration of a solution prepared in a 50%ml plastic (polypropylene) standard flask led to the discovery that there was an error of - 1.7 ml in the volume of the Aask. The results of a subsequent examination of a further thirty plastic flasks-which showed over half to have volume errors outwith the tolerances for Class B glassware-onfirm the need for a reminder of the importance of calibration of standard laboratory ware, even when only moderate accuracy is required. Comparison of values for the coefficient of cubical thermal expansion, y, derived from literature values for the coefficient of linear expansion for polypropylene’ and polymethylpentene2 (1.8-3.0 x 10m4 and 3.5 x low4 deg-‘) with those for borosilicate and soda glass (1.0 x lo-’ and 2.7 x lo-’ deg-‘) made it evident that the Tables for Use in Calibration of Volumetric Glassware3 would not be applicable. A short table of correction factors for plastics with y = 2, 3, 4, 5 and 6 x 10v4 deg- ’ is given in the British Standard for graduated plastic measuring cylinders4 but no indication is given of likely values of y for particular materials, and extensive interpolation would be required in use. The glasssware tables3 are calculated from the equation c=
v,,-
w
l_il+v(-N@t-~W A-a
1 (1)
where C is the correction to be added to the apparent weight in air of the water contained (or delivered), W, to obtain the volume of the vessel at 20”, V,e; c is the density of air at 20” and 760 mmHg, 0.0011994 g/cm3 ; A is the density of the weights, 8.0 g/cm3 (for stainless steel), and pt is the density of water at the temperature t (in “C). Density values for water were calculated from the equation given by Tilton and Taylor,5 then divided by 1.000028 to convert from g/ml (pre-SI definition) to g/cm3. TAL. 28/l+~
Equation (1) was evaluated for values of y from 2.0 x 1o-4 to 5.5 x 10Y4 deg- ’ in steps of 0.1 x 10e4, for a nominal volume of 100 ml, and for temperatures from 5 to 40”, to give a calibration table for each value of y. A series of calibration weighings of lOO-ml polypropylene and polymethylpentene standard flasks was then made, by the procedure recommended for glass flasks6 in which the water used to fill the flasks ranged in temperature from 5 to 40”. The volume at 20” was then calculated from each of several calibration tables for y-values in the region of the literature values. An additional correction of 0.0004 ml/deg was made to compensate for the difference between the temperature of the water and the surrounding air.’ For each set of values (over the whole temperature range) obtained from a particular table, the standard deviation of the calculated volumes was evaluated in order to find which table should be chosen. For polypropylene, the optimum table was the one for y = 3..0 x 10m4 deggr, and for polymethylpentene, the one for y = 4.3 x 10e4 deg-‘. In both cases, the standard deviation obtained by use of the best table was approximately the same as the standard deviation for a series of calibrations made at 20.0”, at which temperature the size of the correction factor is independent of y. The optimum tables are presented here, in the hope that they may be useful to British readers. Others should use them with caution, since different brands of plastic ware may have differing thermal-expansion properties. If there is any doubt, it would be a useful precaution to work only at 20”. Both tables refer to vessels of nominal volume 100 ml: corrections for other volumes can be calculated by simple proportion. It is interesting to note that, although the actual volumes of plastic vessels change with temperature by a much greater amount than do the volumes of glass ones, the weights of water contained vary by rather less. This is illustrated in Table 3.
781
782
ANALYTICAL
DATA
Table 1. Calibration table for polypropylene [nominal capacity 100 ml; coefficient of thermal expansion 3.0 x lo-“ deg-‘; add to weight (g) of distilled water at the temperature of measurement, to obtain volume (ml) at 20”]
5 6 1 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.558 0.531 0.504 0.480 0.456 0.435 0.414 0.395 0.377 0.360 0.345 0.330 0.317 0.305 0.294 0.284 0.276 0.268 0.261 0.256 0.251 0.247 0.244 0.243 0.242 0.242 0.243 0.244 0.247 0.250 0.255 0.260 0.266 0.273 0.280 0.288
0.555 0.528 0.502 0.477 0.454 0.433 0.412 0.393 0.375 0.359 0.343 0.329 0.316 0.304 0.293 0.284 0.215 0.267 0.261 0.255 0.251 0.247 0.244 0.242 0.242 0.242 0.243 0.245 0.241 0.251 0.255 0.260 0.266 0.273 0.281 0.289
0.553 0.525 0.499 0.475 0.452 0.430 0.410 0.391 0.373 0.357 0.342 0.328 0.315 0.303 0.292 0.283 0.274 0.267 0.260 0.255 d.250 0.247 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.251 0.256 0.261 0.267 0.274 0.282 0.290
0.550 0.523 0.497 0.473 0.450 0.428 0.408 0.389 0.372 0.355 0.340 0.326 0.314 0.302 0.291 0.282 0.273 0.266 0.260 0.254 0.250 0.246 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.252 0.256 0.262 0.268 0.275 0.283 0.291
0.547 0.520 0.494 0.470 0.448 0.426 0.406 0.388 0.370 0.354 0.339 0.325 0.312 0.301 0.290 0.281 0.273 0.265 0.259 0.254 0.249 0.246 0.244 0.242 0.242 0.242 0.243 0.245 0.248 0.252 0.257 0.262 0.268 0.276 0.283 0.292
0.544 0.517 0.492 0.468 0.445 0.424 0.404 0.386 0.368 0.352 0.337 0.324 0.311 0.300 0.289 0.280 0.272 0.265 0.258 0.253 0.249 0.246 0.243 0.242 0.242 0.242 0.243 0.246 0.249 0.252 0.257 0.263 0.269 0.27;
0.541 0.515 0.489 0.466 0.443 0.422 0.402 0.384 0.367 0.351 0.336 0.322 0.310 0.299 0.288 0.279 0.271 0.264 0.258 0.253 0.249 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.249 0.253 0.258 0.263 0.270 0.271 0.285 0.294
0.539 0.512 0.481 0.463 0.441 0.420 0.400 0.382 0.365 0.349 0.335 0.321 0.309 0.297 0.287 0.278 0.270 0.263 0.257 0.252 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.249 0.253 0.258 0.264 0.270 0.278 0.286 0.295
0.536 0.510 0.485 0.461 0.439 0.418 0.399 0.380 0.363 0.348 0.333 0.320 0.308 0.296 0.286 0.277 0.269 0.263 0.257 0.252 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.246 0.250 0.254 0.259 0.265 0.271 0.279 0.287 0.296
0.533 0.507 0.482 0.459 0.437 0.416 0.397 0.379 0.362 0.346 0.332 0.318 0.306 0.295 0.285 0.277 0.269 0.262 0.256 0.251 0.248 0.245 0.243 0.242 0.242 0.242 0.244 0.247 0.250 0.254 0.259 0.265 0.272 0.279 0.288 0.297
0.2a4 0.293
ANALYTICAL
783
DATA
Table 2. Calibration table for polymethylpentene [nominal capacity 100 ml; coefficient of thermal expansion 4.3 x lo-’ deg-’ ; add to weight (g) of distilled water at the temperature of measurement, to obtain volume (ml) at 20”] Temp.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
0.753 0.712 0.673 0.636 0.599 0.564 0.531 0.499 0.468 0.438 0.410 0.382 0.356 0.331 0.307 0.284 0.263 0.242 0.222 0.204 0.186 0.170 0.154 0.139 0.125 0.112 0.100 0.089 0.079 0.070 0.061 0.053 0.047 0.040 0.035 0.031
0.749 0.708 0.669 0.632 0.596 0.561 0.528 0.496 0.465 0.435 0.407 0.380 0.354 0.329 0.305 0.282 0.261 0.240 0.221 0.202 0.185 0.168 0.152 0.138 0.124 0.111 0.099 0.088 0.078 0.069 0.060 0.053 0.046 0.040 0.035 0.030
0.745 0.704 0.666 0.628 0.592 0.558 0.524 0.492 0.462 0.432 0.404 0.377 0.351 0.326 0.303 0.280 0.259 0.238 0.219 0.200 0.183 0.166 0.151 0.136 0.123 0.110 0.098 0.087 0.077 0.068 0.059 0.052 0.045 0.039 0.034 0.030
0.741 0.700 0.662 0.625 0.589 0.554 0.521 0.489 0.459 0.429 0.401 0.374 0.349 0.324 0.300 0.278 0.256. 0.236 0.217 0.198 0.181 0.165 0.149 0.135 0.121 0.109 0.097 0.086 0.076 0.067 0.059 0.05 1 0.045 0.039 0.034 0.030
0.737 0.697 0.658 0.621 0.585 0.551 0.518 0.486 0.456 0.427 0.399 0.372 0.346 0.321 0.298 0.276 0.254 0.234 0.215 0.197 0.179 0.163 0.148 0.133 0.120 0.107 0.096 0.085 0.075 0.066 0.058 0.051 0.044 0.038 0.033 0.029
0.732 0.693 0.654 0.617 0.582 0.548 0.515 0.483 0.453 0.424 0.396 0.369 0.344 0.319 0.296 0.273 0.252 0.232 0.213 0.195 0.178 0.162 0.146 0.132 0.119 0.106 0.095 0.084 0.074 0.065 0.057 0.050 0.043 0.038 0.033 0.029
0.728 0.689 0.650 0.614 0.578 0.544 0.511 0.480 0.450 0.421 0.393 0.366 0.341 0.317 0.293 0.271 0.250 0.230 0.211 0.193 0.176 0.160 0.145 0.131 0.117 0.105 0.094 0.083 0.073 0.064 0.056 0.049 0.043 0.037 0.032 0.029
0.724 0.685 0.647 0.610 0.575 0.541 0.508 0.477 0.447 0.418 0.390 0.364 0.339 0.314 0.291 0.269 0.248 0.228 0.209 0.191 0.174 0.158 0.143 0.129 0.116 0.104 0.092 0.082 0.072 0.064 0.056 0.048 0.042 0.037 0.032 0.028
0.720 0.681 0.643 0.606 0.571 0.538 0.505 0.474 0.444 0.415 0.388 0.361 0.336 0.312 0.289 0.267 0.246 0.226 0.207 0.190 0.173 0.157 0.142 0.128 0.115 0.103 0.091 0.081 0.071 0.063 0.055 0.048 0.042 0.036 0.032 0.028
0.716 0.677 0.639 0.603 0.568 0.534 0.502 0.471 0.441 0.412 0.385 0.359 0.334 0.310 0.287 0.265 0.244 0.224 0.206 0.188 0.171 0.155 0.141 0.127 0.114 0.102 0.090 0.080 0.071 0.062 0.054 0.047 0.041 0.036 0.031
30 31 32 33 34 35 36 37 38 39 40
Table 3. Effect of temperature on lOO-ml vessels Borosilicate glass y=l.Ox 10-s Temperature “C 5 10 15 20 25 30 35 40
AV -0.015 -0.010 -0.005 0.0 0.005 0.010 0.015 0.020
W, 1.0016 1.0014 1.0008 1.0 0.9989 0.9975 0.9960 0.9942
Soda glass 7=2.7x 1O-5 AV -0.041 - 0.027 -0.014 0.0 0.014 0.027 0.041 0.054
W, 1.0014 1.0012 1.0098 1.0 0.9990 0.9977 0.9962 0.9945
Polypropylene y = 3.0 x 1o-4 AV -0.45 -0.30 -0.15 0.0 0.15 0.30 0.45 0.6
W, 0.9973 0.9985 0.9994 1.0 1.0003 1.0904 1.0003 l.tXlOO
Polymethylpentene y = 4.33 x 1o-4 AV -0.645 -0.43 -0.215 0.0 0.215 0.43 0.645 0.86
W, 0.9953 0.9972 0.9987 1.0 1.0001 1.0017 1.0023 1.0026
AV = difference in volume from 100.00 ml. W, = (weight of water contained)/(weigbt of water contained at 20”).
REFERENCES
1. G. W. C. Kaye and T. H. Laby, Tables of Physical and Chemical Constants, 14th Ed., p. 253. Longmans, London, 1973. 2. Encyclopedia of Polymer Science and Technology, Vol. 9, Interscience, New York, 1968.
3. B.S. 1797: 1968. 4. B.S. 5404: Part 2: 1977. 5. L. W. Tilton and J. K. Taylor, .I. Res. Nat!. Eur. Stds., 1937,18,205. 6. B.S. 1792: 1960. .7. I. M. Kolthoff and P. J. Elving, eds., Treatise on Analyrical Chemistry, Part 1, Vol. 7, p. 4312. Interscience, New York, 1967.