Molecular weight expected errors

Expected errors for this method are 4-5 percent. At higher pressures, a pressure correction using Eq. (2-130) may be used. The mixture is treated as a hypothetical pure component with mixture critical properties obtained via Eqs. (2-5), (2-8), and (2-17) and with the molecular weight being mole-averaged. 

In the calculation of molecular weight, g/mole, there would be less HA available than expected. Therefore, in the titration against NaOH, it would take less NaOH than expected to reach the equivalence point. This error would cause a larger MW than expected, because the denominator (moles) would be smaller. 

It must be noted that the present analysis of Mc serves only as an approximate indication of the expected values of molecular weight between crosslinks. If one recalls that the values of x actor and porosity p used here are determined from best fitting of data by other investigators for similar coals it is evident that this analysis is subject to error. Experimental data for x and P are being obtained for our coals in our laboratory. However, this contribution shows how experimental data can be used to improve determination of Mc and to present, for the first time, approximate values of this important physical parameter of the crosslinked structure of coals. 

D. To calculate the molecular weight averages and intrinsic viscosity you will have to extrapolate the calibration curves outside the range of the standards in order to obtain appropriate values of Mt or J at elution volumes that are less than 23.3. Would you expect tins to introduce significant errors Test your answer by calculations using different assumptions. 

Within the experimental error limits, the surface occupied by28 polyester molecule is constant and in the range of 0.45-0.50 nm. Assuming, as previously shown, that a neutralized end group has a surface of 0.63 nm, about 75 % of the polyester chains are therefore located on the particle surface. As expected, the specific surface of the latex decreases with increasing polyester surfactant molecular weight. 

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