What is the most efficient way of calculating molar mass of large molecules?

Question

Thanks.

Answer 1

Killodaltons (kDa)

Answer 2

Not certain what you mean by 'most efficient', but MM is calculated in the same manner, large or small...just more 'donkey labor' as the molecule increases in size.

If you know the structure or have the molecular formula, simply count  the number of each type of atom and multiply by its atomic weight, then add them all up...eg

dodecanol is CH3(CH2)10CH2OH

C = 12 x 12 =144

H = 26 x 1 =....26

O = 1 x 16 =....16

Total =...........186

(If you require more significant figures, consult an AW chart, and use as many figures as necessary...eg H is closer to 1.008)

Hope this is what you wanted...if not, add details and I'll try again :-))

ADDED LATER

I offered how to CALCULATE MM, but see now that you want means of MEASURING it.

The only non-destructive (more or less) methods I'm aware of are BP elevation, FP depression, and osmotic pressure measurments...all of which require a solution of the unknown.

You might look into these methods to see if any is suitable for your material.