How to calculate the Number Average Molecular Weight for Polycarbonate
The number average molecular weight is the total weight of the sample divided by the number of molecules in the sample.
In mathematical form, the total mass is NiMi, where Ni is the number of molecules of weight Mi.
For example is you have the following data
Number of Molecules, Ni | Mass of Each Molecule, Mi | Total Mass of Each Type of Molecule, NiMi |
---|---|---|
1 | 20000 | 20000 |
3 | 24000 | 72000 |
5 | 27000 | 135000 |
8 | 30000 | 240000 |
5 | 33000 | 165000 |
3 | 35000 | 105000 |
2 | 40000 |
80000 |
Then NiMi, = 817000, The total number of molecules is summation of the first column which is 27
So number average molecular weight will be 817000/27 = 30259 is the number avergae molecular weight.
Get Answers For Free
Most questions answered within 1 hours.