31. The boiling point is 177 �C . The average molar mass is 138.25 g / mol. 32. A useful convention for normal laboratory work is to quote molar masses to two decimal places for all calculations. 33. The next step is to convert the time at which the samples eluted into a measurement of molar mass . 34. To obtain molar mass , light scattering instruments need to measure the intensity of light scattered at zero angle. 35. In practice, due to the existence of isotopes, molar masses are used instead when calculating the mass ratio. 36. Despite minor differences to define all formulations the predicted molar mass of dry air and below table shows these differences. 37. The molar mass distribution of a polymer sample depends on factors such as chemical kinetics and work-up procedure. 38. After multiplication with the appropriate molar masses of the batch ingredients one obtains the batch mass fraction matrix M B: 39. Where is the molar mass , is the pressure, is the universal gas constant, and is the absolute temperature. 40. However, the polymer may be defined by a known precursor or reaction ( s ) and the molar mass distribution.
